14 common network ports you should know

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The physical ports on your computer allow communicate with peripheral devices such as your keyboard and mouse and to connect with internet devices via Ethernet cables.

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Witin computer networking, ports serve a similar purpose. When a computer system seeks to connect to another computer, the port serves as a communication endpoint. It is also possible for different services running on the same computer to expose various ports and communicate with one another using these ports. In simple terms, if a software application or service needs to communicate with others, it will expose a port. Ports are identified with positive 16-bit unsigned integers, ranging from 0 to 65535. Other services use this port number to communicate with the service or app. Port numbers are divided into three ranges: well-known ports, registered ports, and dynamic or private ports.

Well-known ports (also known as system ports ) are numbered from 0 through 1023. For example, to connect to the host example.com via SSH, I would use this command:

In this example, -v stands for verbose, and you should see output similar to this:

As shown, SSH is trying to connect to example.com using port number 22. You may use the -p option to specify another port number; otherwise, SSH will default to 22.

The Internet Assigned Numbers Authority (IANA) has assigned port numbers to commonly used services like SSH, FTP, HTTP, HTTPS, and others. Here are some of the most common ones:

In my work, I most commonly come across ports 80, 443, 20, 21, 22, 23, 25, and 53. Knowing these ports can help you work more efficiently.

What ports do you use the most, and why?

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Common Ports Cheat Sheet: The Ultimate List

Common Ports Cheat Sheet

Perhaps you’re angsty that you’ve forgotten what a certain port number meant. Rest assured, you don’t have to remember all 65,535 port numbers. With so much information to remember, it’s understandable if you forget a common port. That’s why we put together this cheat sheet of common network ports for you.

A crucial domain of expertise in IT-related certifications such as Cisco Certified Network Associate (CCNA) and those of CompTIA is port numbers and associated services , which this common ports and protocols cheat sheet covers. If you want to remember a port number or protocol, this cheat sheet will help everyone, from students to professionals.

Get a copy of this common ports cheat sheet here to keep on your desk. When you're ready, scroll below to find the port you’re looking for.

Common Ports Cheat Sheet Search

Search our Common Ports cheat sheet to find the right cheat for the term you're looking for. Simply enter the term in the search bar and you'll receive the matching cheats available.

Common Ports and Protocols Cheat Sheet

The following tables cover services (and malware) that use common TCP ports and some UDP or SCTP ports.

Well-known/System Ports: 0 – 1023

Registered ports: 1024 – 49151, dynamic/private ports: 49152 – 65535.

You may use these ports for custom applications free from concerns that it may clash with existing processes.

The Most Common Ports for Exams

If you’re studying for IT certifications such as CCNA , focus on these ports:

We hope that you found this cheat sheet useful. Familiarity with ports and protocols is vital to building secure applications and troubleshooting problems on computer networks. Whether you're studying or working, this cheat sheet of common network ports will help you in academic and professional settings.

For further resources, or if you’re curious about how ports and protocols fit into cyber security, look into network security courses available with our StationX Accelerator Program .

Frequently Asked Questions

FTP: ports 20-21; SSH/SCP: port 22; HTTP: 80; HTTPS: 443; POP3: 110; POP3 over SSL: 995; IMAP: 143; IMAP over SSL: 993. We recommend you download the graphic in Well-known/System Ports .

It depends on whether you’re referring to system ports (1024) or want to include ports registered with apps (49152) because system ports range from 0 through 1023, and registered ports span 1024 – 49151.

FTP: ports 20-21; SSH/SCP: port 22; Telnet: 23; SMTP: 25; DNS: 53; HTTP: 80; POP3: 110; IMAP: 143; HTTPS: 443.

FTP: port 21; SSH/SCP: 22; Telnet: 23; SMTP: 25; DNS: 53; POP3: 110; IMAP: 145; HTTP: 80; HTTPS: 443; MySQL: 3306; RDP: 3389; VNC: 5900.

The following are the three types of ports with corresponding port number ranges: • Well-known/System ports: 0 – 1023 • Registered ports: 1024 – 49151 • Dynamic/Private ports: 49152 – 65535

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Nathan House is the founder and CEO of StationX. He has over 25 years of experience in cyber security, where he has advised some of the largest companies in the world. Nathan is the author of the popular "The Complete Cyber Security Course", which has been taken by over half a million students in 195 countries. He is the winner of the AI "Cyber Security Educator of the Year 2020" award and finalist for Influencer of the year 2022.

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Nathan, thank you for supplying this sheet. It comes in handy when you’re trying to remember what a particular port is used by.

Our pleasure.

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Thank you, Nathan

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This is a great single point to reference all default ports. Thank you!!!

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Very good, it will be in front of me!

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Ports on computers are required for networking, and without them, the computer would be completely isolated and it would be unable to communicate with other devices. So thank you for proving this list of the Common TCP and UDP Port numbers.

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After resetting my router cause the password got changed and all the setting were changed to gain access to my computer. I spent about 20 minutes setting up the router. It appears the router never got set up from the cable company when it was installed. So if you have not done so lately check your router and settings.

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Cool, Thanks for sharing!!

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Sorry Nathan, i did not leave a comment for this “Common Ports” Chart last-week. I am glad i signed up to your news letter you are a good researcher. thank you for sharing with us all..

' src=

Nathan, I must thank you for these cheat sheets! They’ve been great on my learning and certification journey!

Thank you too!

' src=

Really really useful.Thanks a lot!!

' src=

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50 Common Ports You Should Know

Port number is a 16-bit numerical value that ranges from 0 to 65535. Well-known port (0-1023), registered port (1024-49151), and dynamic port is three types of port number space. (49152-65535).

These ports can be opened and used by software applications and operating system services to send and receive data over networks (LAN or WAN) that employ certain protocols (eg TCP, UDP).

For example, we use 80 for HTTP-web-based plain-text surfing and 443 for HTTPS-web-based encrypted websites in our daily work.

To conclude, a port is a logical form to identify system activities or various network services used to create local or network-based communications.

What are the functions of ports?

When interacting over the Internet, TCP and UDP protocols make connections, recompile data packages after the transfer, and then deliver them to applications on the recipient’s device. For this handover to work, the operating system must install and open the gateway for the transfer. Each door has a unique code number. After transmission, the receiving system uses the port number to determine where the data should be sent. The port numbers of the sender and receiver are always included in the data packet.

Ports are assigned sequential numbers from 0 to 65535. Some of these codes are standardized, meaning they are assigned to certain uses. Since code numbers are universally recognized and permanently assigned, these standard ports are also known as well-known ports. Registered ports are those that organizations or software developers have registered for their applications. Registration is handled by the Internet Assigned Numbers Authority (IANA). A diverse selection of dynamically assigned port numbers is also available. For example, when viewing websites, browsers use these ports. After that, the phone number is free again.

Why is it important to know these ports?

Any security researcher, bug bounty hunter, or anyone working with service configuration would benefit from this. Knowing how to do more thorough scans such as version detection or known vulnerabilities for ancient services that are still operating in the infrastructure, especially when using tools like Nmap, is handy when getting to know these protocols and services. 

The most 50 significant ports are listed here:

The following are some of the most common service names, transport protocol names, and port numbers used to differentiate between specific services that employ TCP, UDP, DCCP, and SCTP.

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Port Numbers Used for Computer Networks

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What Is a Port Number in Networking?

How port numbers work, when you may need to take action with port numbers, open and closed ports.

In computer networking , port numbers are part of the addressing information used to identify the senders and receivers of messages. They are associated with TCP/IP network connections and might be described as an add-on to the IP address .

Port numbers allow different applications on the same computer to share network resources simultaneously. Home network routers and computer software work with these ports and sometimes support configuring port number settings.

Networking ports are software-based and unrelated to physical ports that network devices have for plugging in cables.

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Port numbers relate to network addressing . In TCP/IP networking, both TCP and UDP use a set of ports that work together with IP addresses.

These port numbers work like telephone extensions. Just as a business telephone switchboard can use the main phone number and assign each employee an extension number, a computer can have a main address and a set of port numbers to handle incoming and outgoing connections.

In the same way that all employees within a building can use one phone number, one IP address can be used to communicate with various applications behind one router. The IP address identifies the destination computer, and the port number identifies the specific destination application.

This is true whether it's a mail application, file transfer program, or web browser. When you request a website from a web browser, the browser communicates over port 80 for HTTP . Then, the data is sent back over the same port and displays in the program that supports that port (the web browser).

In both TCP and UDP, port numbers start at 0 and go up to 65535. The lower ranges are dedicated to common internet protocols such as port 25 for SMTP and port 21 for FTP.

To find the specific values used by certain applications, view a list of ​ the most popular TCP and UDP port numbers . For Apple software, view the TCP and UDP ports used by Apple software products .

The network hardware and the software automatically process port numbers. Casual users of a network do not see these port numbers and don't need to take any action involving their operation. Individuals can, however, encounter network port numbers in certain situations.

Network administrators may need to set up port forwarding to allow the port numbers of specific applications to pass through a firewall . On home networks, a broadband router supports port forwarding on its configuration screens. A common application of homeport forwarding is for online games that use non-standard ports that the router's built-in firewall blocks.

Network programmers sometimes need to specify port numbers in their code, such as in socket programming.

A website URL will sometimes require a specific TCP port number to be included. For example, http://localhost:8080/ uses TCP port 8080 rather than the default port 80. This is usually seen in software development environments more than in mainstream consumer usage.

Network security enthusiasts also frequently discuss the port number used as a key aspect of attack vulnerabilities and protections. Ports can be classified as either open or closed. Open ports have an associated application that listens for new connection requests, and closed ports do not.

A process called network port scanning detects test messages at each port number to identify which ports are open. Network professionals use port scanning as a tool to measure exposure to attackers and often lock down networks by closing non-essential ports. Hackers, in turn, use port scanners to probe networks for open ports that may be exploitable.

You can use the netstat command in Windows to see information regarding active TCP and UDP connections.

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UDP and TCP ports: A list of the most important ports

UDP and TCP ports: A list of the most important ports

TCP and UDP  are used to connect two devices over the Internet or other networks. However, to give data packages an entrance to the PC or server at the other end of the connection, the “doors” have to be open. These openings into the system are called ports. For both protocols, there are some known and important ports which you need to know when developing web apps.

What do ports do?

Well-known ports, registered ports.

When communicating via the Internet, the two protocols TCP and UDP establish the connection, compile data packages again after transfer, and then hand them over to the programs addressed on the recipient’s device. For this handover to work, the operating system must create entrances and open them for the transfer. Every entrance has a specific code number . After the transfer, the receiving system knows where the data has to be delivered based on the port number. The data package always includes two port numbers: the sender’s and the recipient’s.

Ports have consecutive numbers – from 0 to 65536. Some of these code numbers are standardized, which means they are assigned to specific applications . These standard ports are also called well-known ports, as the code numbers are known to all and permanently assigned. There are also registered ports, which organizations or software producers have registered for their applications. The Internet Assigned Numbers Authority (IANA) is responsible for registration. There is also a wide range of port numbers that are assigned dynamically. For example, browsers use these ports when visiting a website. The number is then free again afterwards.

List of the most important ports

Among the over 65,000 ports, there are few code numbers that are essential for Internet communication. We want to show you the most important well-known ports and registered ports. Some of these ports are only authorized for one of the two protocols (TCP or UDP). There are also ports that were not officially registered for the service in question, but have established themselves unofficially. Some ports have double assignments.

Ports numbered 49152 and higher are dynamic ports. They are not assigned by IANA. Any application can use these ports locally or globally in a dynamic way. As a result, it could easily be the case that one of these ports is already occupied.

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TCP/IP

Without TCP/IP protocols, you wouldn’t be able to read the words on this page. TCP and IP, the two foundational protocols of the suite, along with other related sets of rules, define how computers communicate over the Internet and other networks. In fact, the standards are so established that every device on the Internet follows these protocols to ensure the smooth transfer of data.

Remote procedure call (RPC) – efficient communication in client-server architectures

Remote procedure call (RPC) – efficient communication in client-server architectures

Due to increasing globalization, processes for connecting and networking digital infrastructures are becoming increasingly important. The remote procedure call (RPC) plays a key role in this context, as it enables efficient inter-process communication designed for task distribution in networked client-server architectures.

RPC server: what should you do if the RPC server is unavailable?

RPC server: what should you do if the RPC server is unavailable?

If the RPC server is unavailable, Windows will display the error code 0x800706BA. This means the network communication between the client and the server has been interrupted. The problem occurs fairly regularly in Windows 10. In this guide, we explain what the RPC server error message means and how you can fix it yourself without any expert network knowledge.

Network News Transfer Protocol (NNTP)

Network News Transfer Protocol (NNTP)

As a global computer network, the Internet provides the perfect foundation for gathering and distributing information. The World Wide Web, the most well-known Internet service, convincingly proves this fact. The older Usenet benefits from the Internet’s global network as well. In order to be able to transfer data, it relies on the unique NNTP, which is the focus of this article.

NTLM (NT LAN Manager)

NTLM (NT LAN Manager)

The NTLM protocol was a practical solution for Windows devices for a long time: A user just had to sign in once and then gain direct access to various network services. However, this authentication method is now considered unsafe and is no longer in use. How does NTLM work, and why do users now prefer to use Kerberos?

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50 Common Ports You Should Know

Introduction.

In the world of computer networking, ports play a crucial role in facilitating communication between different devices. A port can be defined as a logical channel through which information streams between two devices. Each port has a unique number assigned to it, known as a port number. Understanding port numbers and their comparing administrations is fundamental for anybody who works with computer systems.

In this article, we'll examine 50 of the most common ports that you should know. These ports are assembled into different types based on their characteristics and utilization. We'll investigate their highlights, significance, and centrality in computer organizing.

Discuss About 50 Common Ports You Should Know?

These ports are used to facilitate communication between devices on the network and are essential for network administrators and IT professionals to understand.

Every port in computer networking is associated with a specific protocol or service, and each protocol or service is assigned a standard port number by the Internet Assigned Numbers Authority (IANA). These would be organized into three ranges - well-known ports (0 to 1023), registered ports (1024 to 49151), and dynamic/private ports (49152 to 65535).

The article gives a comprehensive list of the 50 most commonly utilized ports, their related conventions, and the sorts of administrations that ordinarily utilize them. It too incorporates a brief clarification of how to utilize harbor filtering instruments to identify open ports and vulnerabilities.

Well-Known Ports

Well-known ports are those ports whose numbers range from 0 to 1023. They are assigned to specific services and protocols, and their numbers are standardized by the Internet Assigned Numbers Authority (IANA). Some common well-known ports include −

Port 80: HTTP (HyperText Transfer Protocol)

Port 21: FTP (File Transfer Protocol)

Port 25: SMTP (Simple Mail Transfer Protocol)

Port 22: SSH (Secure Shell)

Port 443: HTTPS (HyperText Transfer Protocol Secure)

Port 53: DNS (Domain Name System)

Registered Ports

Registered ports are those ports whose numbers range from 1024 to 49151. They are assigned to user processes or applications by the IANA upon request. Some commonly registered ports include −

Port 3306: MySQL Database

Port 5432: PostgreSQL Database

Port 3389: Remote Desktop Protocol (RDP)

Port 27017: MongoDB Database

Port 1521: Oracle Database

Dynamic or Private Ports

These ports whose numbers range from 49152 to 65535. They are used by client applications to initiate communication with servers. Some common dynamic or private ports include −

Port 49152: Windows RPC (Remote Procedure Call)

Port 5353: mDNS (Multicast Domain Name System)

Port 5672: AMQP (Advanced Message Queuing Protocol)

Port 5355: LLMNR (Link-Local Multicast Name Resolution)

Port 49153: Windows RPC (Remote Procedure Call)

Impact of ports on Computer Networks

Port numbers play a vital role in the security of computer networks.

Misconfigured ports can lead to security breaches and data leaks.

Understanding port numbers and their corresponding services can help in the identification and prevention of cyber-attacks.

Significance of ports

Ports are the backbone of computer organizing and empowering communication between different devices and applications.

Ports encourage the exchange of information between different protocols and administrations.

The standardization of well-known ports by the IANA guarantees that different devices can communicate with each other consistently.

Some other common ports are

Telnet (23) - Telnet protocol to ensure effective communication along with the remote server.

POP3 (110) - Post Office Protocol version 3 for email retrieval.

IMAP (143) - Internet Message Access Protocol for email retrieval.

DHCP (67/68) - Dynamic Host Configuration Protocol for IP address allocation.

NTP (123) - Network Time Protocol for time synchronization.

SNMP (161/162) - Simple Network Management Protocol to verify the functionality of the network and management of network.

SMB (445) - Server Message Block protocol for file sharing and printer sharing.

AFP (548) - Apple Filing Protocol for file sharing between Macs.

NetBIOS (137-139) - NetBIOS protocol for network communication between Windows devices.

HTTP Proxy (8080) - HTTP proxy server.

SOCKS (1080) - SOCKS proxy server.

MySQL (3306) - MySQL database server.

MSSQL (1433) - Microsoft SQL Server database server.

Oracle (1521) - Oracle database server.

LDAP (389/636) - Lightweight Directory Access Protocol for directory services.

SMB2 (5722) - SMB version 2 protocol.

IKE (500) - Internet Key Exchange protocol for VPN connections.

L2TP (1701) - Layer 2 Tunneling Protocol for VPN connections.

PPTP (1723) - Point-to-Point Tunneling Protocol for VPN connections.

SIP (5060/5061) - Session Initiation Protocol for VoIP communication.

RTP (16384-32767) - Real-time Transport Protocol for audio and video transmission.

RTCP (16384-32767) - Real-time Control Protocol for audio and video transmission.

HTTPS Proxy (3128) - HTTPS proxy server.

Squid (3128) - Squid proxy server.

VNC (5900) - Virtual Network Computing for remote access.

IRC (6667/6697) - Internet Relay Chat for real-time communication.

Bonjour (5353) - Bonjour protocol for network discovery and communication.

NFS (2049) - Network File System for file sharing.

Redis (6379) - Redis key-value store.

Memcached (11211) - Memcached distributed memory caching system.

Rsync (873) - Remote synchronization for file transfers.

Zeroconf (5353) - Zero Configuration Networking for automatic network configuration.

XMPP (5222/5223) - Extensible Messaging and Presence Protocol for instant messaging.

VMware vSphere Client (443) - VMware vSphere Client for virtualization.

In conclusion, understanding the common ports used in computer networking is essential for IT professionals and network administrators. Being aware of these ports can help them troubleshoot network issues and ensure smooth communication between devices on the network.

Pranavnath

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14 Common Network Ports You Should Know

The physical ports on your computer allow communicate with peripheral devices such as your keyboard and mouse and to connect with internet devices via Ethernet cables.

Within computer networking, ports serve a similar purpose. When a computer system seeks to connect to another computer, the port serves as a communication endpoint. It is also possible for different services running on the same computer to expose various ports and communicate with one another using these ports. In simple terms, if a software application or service needs to communicate with others, it will expose a port. Ports are identified with positive 16-bit unsigned integers, ranging from 0 to 65535. Other services use this port number to communicate with the service or app. Port numbers are divided into three ranges:  well-known  ports,  registered  ports, and  dynamic  or  private  ports.

Well-known ports  (also known as  system ports ) are numbered from 0 through 1023. For example, to connect to the host  example.com  via SSH, I would use this command:

In this example, -v stands for verbose,…

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Ports for Network+, Security+, and SSCP Exams

If you’re planning on taking a certification exam such as CompTIA Security+ , CompTIA Network+ , or SSCP you should have many of the well-known ports memorized. The objectives for the CompTIA Network+ exam lists many of the protocols and the ports spelling out exactly what you need to know. Similarly, the objectives for the CompTIA Security+ exam lists several protocols with a statement to identify the ports for each. The SSCP exam objectives are very generic but do indicate port numbers are needed.

Well known port numbers are matched to specific protocols and when you see the port, you should be able to identify the protocol. Sometimes you may be given the protocol and be required to identify the port. There are 1024 well known TCP and UDP (numbered 0 through 1023) but you don’t need to memorize them all. However, you do need to know certain ports for the CompTIA Security+, CompTIA Network+, and SSCP exams.

Logical Ports

The well-known ports are logical ports and have nothing to do with physical ports. For example, port 80 is the port used for Hypertext Transfer Protocol (HTTP) and port 443 is the port used for Hypertext Transfer Protocol Secure (HTTPS).

In contrast, a physical port on a switch or router is used to make a physical connection between devices. You can touch the physical port while the logical port is simply a number embedded in the packet.

Every packet has both a source port and a destination port along with a source IP address and a destination IP address. The IP address is used to get the packet to the destination system and when the packet is received, TCP/IP uses the port information to determine how to handle the packet. This blog on Understanding Ports for Security+ describes the process of how logical ports are used in more detail.

TCP vs UDP Ports

Each of these logical ports are technically identified as either a Transmission Control Protocol (TCP) port or a User Datagram Protocol (UDP) port depending on which transport protocol they use. For example, HTTP can use either UDP port 80 or TCP port 80. It almost always uses TCP for guaranteed delivery but both TCP port 80 and UDP port 80 are reserved for HTTP.

Some protocols use only the UDP port. For example, Trivial File Transport Protocol (TFTP) uses UDP port 69 but not TCP port 69.

As you advance in the IT field, you’ll find that you need to know whether a protocol is using a TCP port or a UDP port. However for these exams, this depth of knowledge is rarely needed. Instead, you should focus on memorizing the port number. If you want to know specifically which transport protocol is used for any protocol, check out Wikipedia’s list of TCP and UDP port numbers .

Interestingly, Internet Assigned Numbers Authority (IANA) previously identified which transport protocol was used for each port in their Service Name and Transport Protocol Port Number Registry . However, they seem to have defaulted to just listing both TCP and UDP for each port. For example, Telnet (defined in RFC 854 ) only uses TCP port 23, not UDP. However, IANAs port number registry lists both TCP and UDP for Telnet.

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Network+ Ports

When preparing for the Network+ exam, you should know these ports.

When you know the ports and understand the protocols, questions are much easier to answer. For example, consider this practice test question that could be in a Network+, Security+, or SSCP exam:

Q. What port do you need to close to block outgoing email?

C. Port 110

D. Port 443

Answer at the end of the blog.

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Security+ Ports

When preparing for the Security+ exam, you should know these ports.

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The list of SSCP ports is a little easier for me to create. It’s simply all of the ports listed in the previous two tables. The (ISC)2 objectives do not list specific ports that you need to know but instead include the words “Commonly Used Ports and Protocols”. Theoretically, they can ask you about any of the ports but you’re unlikely to see anything other than what is listed here. If you do, please let me know .

Practice Test Question Answer

Port 25 is used for SMTP and SMTP is used for outgoing email.

Port 22 is used for SSH, SFTP, and SCP but not for email.

Port 110 is used for POP3 but POP3 is only used for incoming email, not outgoing email.

Port 443 is used for HTTPS, not email.

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port numbers you should know

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port numbers you should know

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1 thought on “ ports for network+, security+, and sscp exams ”.

I have often wondered why the test prep books don’t provide this concisely on a page. I’m hoping your book is different. But at least the info is here. I believe the next generation of study aids. For these types of wrote memorization exams will provide mneumonic devices for committing the information to memory for easy recall. I have some ideas in this area and I’ll share them it they work for me and others.

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How to choose open port number?

I installed easyPHP and opened a port on my firewall so that other people can access to my webserver. The default port is 8888. But I am wondering how do you choose a port number? Is it really ambiguous or there is a "prefered" range of port number?

  • port-forwarding

Giacomo1968's user avatar

  • 1 Generally any port is fine. The reason why many apps use ports like 8888 or 8080 is those are non-admin level ports so many end users without admin rights can just start up a server. This works on pro web applications as well. But many times what happens with those applications a front-end web proxy connects 8080 or 8888 to port 80. Generally you should just use port 80 for ease of access. Anything else would require something like 123.456.789.0:8080 or example:8080 . –  Giacomo1968 Jul 24, 2018 at 2:45
  • @JakeGould Thanks for your comment it really helped me.! –  GeneCode Jul 24, 2018 at 2:56
  • Possibly related question: stackoverflow.com/questions/10476987/… –  glenneroo Jul 24, 2018 at 18:48
  • 1 Does this answer your question? Can I serve a website on any port I want to? –  Jim G. Oct 19, 2022 at 14:33

A port number is a 16-bit unsigned integer, thus ranging from 0 to 65535 (although 0 cannot be used for TCP; it has a special meaning for UDP).

You can use pretty much any port number in the range, however there are some guiding rules:

  • (On Unix based systems at least), only root can bind to ports below 1024.
  • You ideally don't want a port typically associated with another common service as this can cause problems with some firewalls.
  • Expanding on (2) above - On Linux systems at least, there is a file /etc/services which has a list of common services - you can use this for guidance.

The "ideal" port to run an HTTP service is port 80, and the ideal port for HTTPS is 443, because those ports are associated with their respective services. If this is not practical (and it often isn't - some routers are too stupid to handle a web interface and port forward externally on the same port), it's common to pick a "themed" port - port 8080 is pretty common, as is port 8000.

psmears's user avatar

  • 1 On modern Windows versions you have to have administrator privileges in order to bind to ports below 1024 as well. –  enkryptor Jul 24, 2018 at 9:54
  • @enkryptor: Which versions are those? Is this documented anywhere? –  u1686_grawity Jul 24, 2018 at 13:25
  • @grawity I believe it's Windows 7 and later. You can also give a permission to a non-admin user for a specific url via netsh http add urlacl –  enkryptor Jul 24, 2018 at 13:31
  • @enkryptor I have nginx running on port 80, non-localhost ip, and I'm not admin in this system. –  Braiam Jul 24, 2018 at 13:52
  • @Braiam good for you –  enkryptor Jul 24, 2018 at 13:53

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port numbers you should know

Briefly

How to port to Telkom in 2024: Full step-by-step guide on how to do it

In present-day South Africa, mobile phone numbers serve as a form of identity. People have maintained the same mobile phone digits for years. Once you get used to your number, you will not want to change it or keep memorising new digits. If you are a subscriber of another mobile network and wish to join the Telkom community, you should learn how to port to Telkom.

Porting a number to Telkom simply means switching from another service provider to Telkom while retaining the digits in your current mobile phone number. The only thing that changes is the prefix for the service provider. If you wish to, you should learn how to port to Telkom right away.

How to port to Telkom: all you should know

Many people avoid switching from one mobile operator to another because they do not wish to lose their original mobile phone digits. Fortunately, porting allows you to retain your number. Only the prefix changes. Discover how to port to Telkom today.

How to port to Telkom mobile (for prepaid customers)

Before you can port your number to Telkom, you need the following things.

  • Your national identity card number
  • A new Telkom SIM card
  • An ICCID number
  • In place of ICCID, ICCIC Telkom refers to a 20-digit number located on the back of your SIM card. It often begins with 89

If you have the information above, you are ready to begin the porting process. Follow the steps below. Note that Telkom's terms and conditions apply.

  • Open the messages app on your mobile phone and type PORTME#IdNumber#ICCID number. Send the message to 0811607678. Note that the standard SMS fees will apply.
  • Wait for the company to respond. Expect a response within two days or less.
  • Follow the instructions given to complete the process.

If you wish, you can also visit the nearest Telkom shop and request the agents to assist you with the porting process.

How to port a postpaid number to Telkom

Postpaid customers cannot port to Telkom via SMS. Instead, they should visit the nearest Telkom shop. The agents will issue a form they must fill out for the porting service to be effected.

How to port from MTN to Telkom

If you have been wondering how to port to Telkom from MTN, below are the steps you should take to port from MTN to Telkom in South Africa.

  • First, visit the nearest shop and purchase a new Telkom SIM card.
  • Next, RICA your new SIM card, i.e., Telkom.
  • After completing the step above, open the Messages app on your mobile phone while it is still fitted with your MTN SIM card.
  • Type PORTME#youridnumber#iccid on your messages. Proofread it to ascertain all the numbers are correct. Send the message to 081 160 7678.
  • Wait for 24 hours for the new SIM card to be activated. Note that once it is activated, your old MTN number becomes inactive.
  • To use your phone, fit your newly activated Telkom SIM card into it.
  • Purchase some Telkom airtime and you will be ready to enjoy the company's services.

How to port MTN to Telkom online

Note that sending a message (as explained above) is the only way to start the porting process at the moment. Telkom is yet to unveil an online porting process.

How to port from Vodacom to Telkom

The steps involved in porting from Vodacom are the same as those explored in the section above (How to port from MTN to Telkom). Follow them to complete the process.

How to port to Telkom using USSD

Currently, there is no USSD that allows you to port numbers to Telkom. Instead, send an SMS to begin the process (as described above).

How to port to Telkom without a SIM card

Kindly note that you will need a Telkom SIM card to complete the porting process. You cannot port without a SIM card.

Porting terms and conditions and things to bear in mind

Below is a list of things you should know before porting to Telkom.

  • You must fulfil any commitments or outstanding payments from your current service provider before porting to Telkom.
  • Telkom may not support some of the products offered by your former service provider.
  • You must buy a new Telkom SIM card before porting.
  • Telkom reserves the right to register your new number.
  • You cannot port a suspended, cancelled, or blacklisted number.
  • You can continue using your mobile phone after porting unless it is locked.

What is a porting number?

Porting means a permanent way of moving a phone number to another provider. The old account associated with the number will be closed.

Can you port your number online?

Telkom does not have an online porting system yet.

How do you port your SIM contact?

You can port your contact by messaging PORTME#youridnumber#iccid to 081 160 7678.

How do you port your number to Telkom online?

There is no online porting system yet. Instead, you should message PORTME#youridnumber#iccid to 081 160 7678.

How can you port your mobile number online?

There is no way to port your mobile number online at the moment. Use the SMS option instead.

Learning how to port to Telkom is easy and straightforward. Follow the guide above to complete the process.

DISCLAIMER: This article is not sponsored by any third party. It is intended for general informational purposes only and does not address individual circumstances. It is not a substitute for professional advice or help and should not be relied on to make decisions of any kind. Any action you take upon the information presented in this article is strictly at your own risk and responsibility!

Briefly.co.za recently published the latest DNA test price in Johannesburg. A paternity test determines whether a certain man is a particular child's genetic or biological dad.

A complete paternity test examines samples from the child, the birth mother, and the alleged father. Besides identifying a child's biological father, a paternity test can determine whether people are biological relatives.

How to port to Telkom in 2024: Full step-by-step guide on how to do it

What does SOS mode on iPhone mean? Symbol appears during AT&T outage Thursday

port numbers you should know

Thousands of customers woke up Thursday morning to an SOS symbol at the top of their iPhones and no service due to a nationwide telecommunications outage .

The outages were impacting AT&T customers the most, although services from Verizon, Cricket Wireless and T-Mobile were also affected. It also began to impact essential public services, including people’s ability to call emergency responders.

The outages have continued through Thursday morning, with more than 70,000 AT&T customers reporting outages as of 8:56 a.m. ET, according to Downdetector.com .

What does the SOS symbol mean, and how does it connect to the outage? Here's what to know.

AT&T down: Tens of thousands report AT&T service outage; Verizon and T-Mobile users also claim issues

What does the SOS symbol on the iPhone mean?

During Thursday's outage, an SOS symbol appeared on the screens of iPhone users with AT&T (in the same place where cell service bars are normally shown).

The SOS symbol can appear in the status bar of iPhones and iPads, meaning devices aren't connected to a cellular network. It also means there is a cellular network "available for emergency calls,"  Apple's support website  states.

The SOS feature is available on iPhones and iPads in the U.S., Australia and Canada.

"When you make a call with SOS, your iPhone automatically calls the local emergency number and shares your location information with emergency services," according to Apple. "In some countries and regions, you might need to choose the service that you need.

After making an emergency call, your iPhone alerts any emergency contacts designated in your phone.

Apple says all iPhone models 14 or later can also use Emergency SOS via satellite to text emergency services when no cellular and Wi-Fi coverage is available.

Contributing: Gabe Hauari and Christopher Cann, USA TODAY.

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AT&T’s network is having problems: What you should know while navigating a phone service outage

AT&T says it has restored wireless coverage after an outage knocked out cellphone service on its network across the U.S. for hours. (Feb. 22) (AP video by Kendria LaFleur)

FILE _ A cellular phone tower is shown on Monday, May 22, 2017 in High Ridge, Mo. A number of Americans are dealing with cellular outages Thursday, Feb. 22, 2024, on AT&T, Cricket Wireless, Verizon, T-Mobile and other service providers, according to data from Downdetector. (AP Photo/Jeff Roberson)

FILE _ A cellular phone tower is shown on Monday, May 22, 2017 in High Ridge, Mo. A number of Americans are dealing with cellular outages Thursday, Feb. 22, 2024, on AT&T, Cricket Wireless, Verizon, T-Mobile and other service providers, according to data from Downdetector. (AP Photo/Jeff Roberson)

  • Copy Link copied

FILE - A woman looks at her phone while watching the sun set as triple-digit heat indexes continue in the Midwest Sunday, Aug. 20, 2023, in Kansas City, Mo. A number of Americans on Thursday, Feb. 22, 204, are dealing with cellular outages on AT&T, Cricket Wireless, Verizon, T-Mobile and other service providers, according to data from Downdetector. AT&T, who was the hardest hit, is actively working to restore service to all of its customers. (AP Photo/Charlie Riedel, File)

FILE -This July 18, 2019, file photo, shows an AT&T retail store in Miami. Customers of AT&T, the country’s largest wireless provider, reported widespread outages on Thursday, Feb. 22, 2024. (AP Photo/Lynne Sladky, File)

FILE - In this Friday, April 30, 2021 file photo, a man uses a mobile phone in New York. A number of Americans on Thursday, Feb. 22, 204, are dealing with cellular outages on AT&T, Cricket Wireless, Verizon, T-Mobile and other service providers, according to data from Downdetector. AT&T, who was the hardest hit, is actively working to restore service to all of its customers. (AP Photo/Mark Lennihan, File)

NEW YORK (AP) — Customers of AT&T, the country’s largest wireless provider, reported widespread outages on Thursday .

Here’s what to know if you are having problems with your phone service.

When did the outage start?

AT&T had more than 58,000 outages around noon ET , in locations including Houston, Atlanta and Chicago. The outages, which began at approximately 3:30 a.m. ET, peaked at around 73,000 reported incidents. The carrier has more than 240 million subscribers, the country’s largest.

FILE - Nokia logo seen in the Mobile World Congress 2023 in Barcelona, Spain, Tuesday, Feb. 28, 2023. Nokia on Thursday reported a double-digit decline in sales and a fall in profit in the last three months of 2023, with the wireless and fixed-network equipment maker saying operators are cutting back on investments into 5G and other technology because of economic uncertainty. (AP Photo/Joan Mateu Parra, File)

What is the SOS mode?

Some AT&T iPhone customers saw SOS messages displayed in the status bar on their cellphones. The message indicates that the device is having trouble connecting to their cellular provider’s network, but it can make emergency calls through other carrier networks, according to Apple Support.

What is Wi-Fi calling?

AT&T urged customers to connect to Wi-Fi to use their phones. Wi-Fi calling is a built-in feature on most Android devices and iPhones and can be turned on under the phone’s settings.

“Some of our customers are experiencing wireless service interruptions this morning. We are working urgently to restore service to them. We encourage the use of Wi-Fi calling until service is restored,” AT&T said in a statement.

If Wi-Fi isn’t available, there are few options for cell phone users. It’s possible to switch services if a phone is unlocked, but that requires signing up online and porting your phone number .

Some apps, including Google Maps, have limited service offline. Payment apps also do not use a phone’s cell service to work and should also be useable.

What caused the outage?

AT&T has stayed mum so far on what caused the outage.

port numbers you should know

Watch CBS News

After AT&T customers hit by widespread outage, carrier says service has been restored

By Brian Dakss, Aimee Picchi

Edited By Anne Marie Lee

Updated on: February 22, 2024 / 8:17 PM EST / CBS News

Customers of numerous U.S. cell service providers reported outages and other service problems early Thursday morning, according to the website  Downdetector.com , which tracks such reports. AT&T had the most by far, with tens of thousands of customers telling Downdetector they had no service.

Customers of T-Mobile, Verizon, UScellular and Consumer Cellular were also reporting issues, though far fewer. T-Mobile and Verizon told CBS News that their networks were operational, although some customers may be encountering problems when trying to reach people on another network.

The reports of AT&T outages appear to have started at around 4 a.m. EST, Downdetector said, then seemed to wane some two hours later, then picked up again and were about 60,000 at 11 a.m. EST.

But by 3:10 p.m. EST on Thursday AT&T  said  the problem had been resolved.

"We have restored wireless service to all our affected customers," AT&T said on its website. "We sincerely apologize to them. Keeping our customers connected remains our top priority, and we are taking steps to ensure our customers do not experience this again in the future."

Later Thursday night, the company attributed the outage to a software bug.

"Based on our initial review, we believe that today's outage was caused by the application and execution of an incorrect process used as we were expanding our network, not a cyber attack," the company  said on its website . "We are continuing our assessment of today's outage to ensure we keep delivering the service that our customers deserve."

United states cluster map showing concentration of user-submitted problem reports over the last 24 hours to Downdetector.com.

Officials: Don't call 911 to test your phone

Earlier in the day, some officials urged people not to call 911 to test whether their phone was working. 

"Many 911 centers in the state are getting flooded w/ calls from people trying to see if 911 works from their cellphone. Please do not do this," the Massachusetts State Police wrote on X, the former Twitter.

Likewise, Chicago's Office of Emergency Management & Communications had a similar message for local residents, noting that on X that people who actually need to get through to 911 should use a landline or find a friend or relative who uses a service other than AT&T and ask them to make the call.

Some municipalities experienced difficulties with 911 service.

The San Francisco Fire Department said in a post on X, "We are aware of an issue impacting AT&T wireless customers from making and receiving any phone calls (including to 911). We are actively engaged and monitoring this. The San Francisco 911 center is still operational."

In North Carolina, the Charlotte-Mecklenburg Police Department said on X at 3:15 a.m. EST that it was "aware of a nationwide outage impacting AT&T cellphone customers this morning. Customers were briefly unable to contact 9-1-1. There are no disruptions to our call center's ability to receive 9-1-1 calls. Service should be returning shortly."

And in Florida, the Flagler County Sheriff's Office posted on X at 6:43 a.m. EST that, "Texts to 911 from affected AT&T users are now being received. If you have an emergency, and cannot dial out, send a text message to 911."

The transit system serving Philadelphia and its suburbs, SEPTA, said on X that, "Due to AT&T communication outages, some trains may reflect a delay, however all trains are operating on or close to schedule."

AT&T outage

As of 8 a.m. ET on Thursday, Downdetector had more than 60,000 reports of service issues from AT&T customers. Most of the complaints were focused on problems with their mobile phones or wireless service. 

Outages were highest in Atlanta, Charlotte, Chicago, Dallas, Houston, Indianapolis, Louisville, Miami and San Antonio, according to Downdetector.

In a statement to CBS News, Verizon said its network was operating normally, although some customers experienced issues earlier Thursday when calling or texting people who use another carrier. It said that it was continuing to monitor the situation. 

A spokesperson for T-Mobile said it didn't experience an outage and that its network was operating normally.

"Downdetector is likely reflecting challenges our customers were having attempting to connect to users on other networks," the spokesperson said.

UScellular also told CBS News that its network was operating normally. 

"We are, however, aware of a disruption that could be impacting UScellular customers attempting to roam on or call customers of another carrier," it said in a statement.

How to turn on Wi-Fi calling

Even if you have no cellular service, you should be able to make phone calls using wireless internet access, which is what AT&T is recommending for its customers. 

To turn on Wi-Fi calling on an iPhone, go to "settings," then "phone" and next click on "Wi-Fi" calling. Apple says you may need to confirm or enter your address for emergency services. 

You'll see "Wi-Fi" in the status bar while you are looking at the control center, which means your phone will use the wireless internet service in your home or office to make calls. 

To turn on Wi-Fi calling on Android phones, Google says to open your phone app, then tap "more settings." Then tap "calls," and from there tap "Wi-Fi calling." If that's not an option on your phone, it means your carrier doesn't provide the option,  according  to Google.

What does SOS mean on my phone?

Some customers reported seeing an "SOS" message on their iPhones. 

This can happen when a cellular service isn't widely available, but your phone is letting you know that it will still work for emergency calls,  according  to Apple.

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COMMENTS

  1. 14 common network ports you should know

    Ports are identified with positive 16-bit unsigned integers, ranging from 0 to 65535. Other services use this port number to communicate with the service or app. Port numbers are divided into three ranges: well-known ports, registered ports, and dynamic or private ports.

  2. Common Ports Cheat Sheet: The Ultimate Ports & Protocols List

    110 SHARES Perhaps you're angsty that you've forgotten what a certain port number meant. Rest assured, you don't have to remember all 65,535 port numbers. With so much information to remember, it's understandable if you forget a common port. That's why we put together this cheat sheet of common network ports for you.

  3. 50 Common Ports You Should Know

    50 Common Ports You Should Know Read Courses Port number is a 16-bit numerical value that ranges from 0 to 65535. Well-known port (0-1023), registered port (1024-49151), and dynamic port is three types of port number space. (49152-65535).

  4. Default Port Numbers You Need to Know as a Sysadmin

    Default Port Numbers You Need to Know as a Sysadmin By Chandan Kumar One of the challenging tasks for an administrator is to remember the default port number. You may remember the most common ones like HTTP, FTP, SSH but if you are working on various technology stacks then it's difficult to remember all of them.

  5. 15 Commonly Used Network Ports Explained

    15 Commonly Used Network Ports Explained Explore key port numbers and related services, learning which transport protocols they use for effective networking. By Bobby Borisov On March 20, 2022 Updated November 16, 2023 Table of Contents [Close] What's a Network Port? Understanding Network Port Ranges Transport Protocols: The Digital Highways

  6. List of TCP and UDP port numbers

    The port numbers in the range from 0 to 1023 (0 to 2 10 − 1) are the well-known ports or system ports. [3] They are used by system processes that provide widely used types of network services.

  7. Port Numbers Used for Computer Networks

    260 Port Numbers Used for Computer Networks TCP and UDP ports explained By Bradley Mitchell Updated on September 17, 2021 Reviewed by Michael Barton Heine Jr In This Article Jump to a Section What Is a Port Number in Networking? How Port Numbers Work When You May Need to Take Action With Port Numbers Open and Closed Ports

  8. What are port numbers and how do they work?

    A port number is a way to identify a specific process to which an internet or other network message is to be forwarded when it arrives at a server. All network-connected devices come equipped with standardized ports that have an assigned number. These numbers are reserved for certain protocols and their associated function.

  9. Common Ports Cheat Sheet: And Ultimate Ports & Protocols List

    Well-known/System Ports: 0 - 1023 Registered Connectivity: 1024 - 49151 Dynamic/Private Ports: 49152 - 65535 To could exercise these ports for habit applications clear from concerns that it can clash includes existing processes. The Most Common Harbors for Exams If you're studying for THERETO certifications such as CCNA, center on these ports:

  10. What is a computer port?

    Port 80: Hypertext Transfer Protocol (HTTP). HTTP is the protocol that makes the World Wide Web possible. Port 123: Network Time Protocol (NTP). NTP allows computer clocks to sync with each other, a process that is essential for encryption. Port 179: Border Gateway Protocol (BGP).

  11. TCP ports / UDP ports: What ports are important and why?

    - IONOS 07/08/2020 Know-how UDP and TCP ports: A list of the most important ports TCP and UDP are used to connect two devices over the Internet or other networks. However, to give data packages an entrance to the PC or server at the other end of the connection, the "doors" have to be open. These openings into the system are called ports.

  12. 50 Common Ports You Should Know

    Introduction In the world of computer networking, ports play a crucial role in facilitating communication between different devices. A port can be defined as a logical channel through which information streams between two devices. Each port has a unique number assigned to it, known as a port number.

  13. How do you decide what port to use?

    8 Answers. I think you've pretty much answered your question as much as is possible; there isn't really a strict rule you can follow here beyond what you've said. But generally: Look at the IANA list and pick a port that's not in use. Pick a port number that is easy to remember. Don't fix the port number in your code.

  14. Common Network Ports

    Those are usually port numbers associated with a service. For example, the web service I just provided was port number 80. And that port number on that server will always be port 80. That is a non-ephemeral port number. On your client device, you're simply using random port numbers to connect to that port 80.

  15. HTTPS Port: What It Is, How to Use It, and More (2023)

    The HyperText Transfer Protocol Secure (HTTPS) port is a secure version of HTTP. It provides a communication channel that secures the data transferred between a server and a web browser using an SSL/TLS certificate that encrypts the web traffic and protects sensitive customer information in transit. In computer networking, there are many ports ...

  16. 14 Common Network Ports You Should Know

    Other services use this port number to communicate with the service or app. Port numbers are divided into three ranges: well-known ports, registered ports, and dynamic or private ports. Well-known ports (also known as system ports) are numbered from 0 through 1023. For example, to connect to the host example.com via SSH, I would use this command:

  17. CompTIA A+ 220-1101

    It's important to know these port numbers and what protocols are often used by a particular port number, but it's also important to know when you would use these protocols. For example, your exam might ask you what port number is used by an application that transfers data in a particular way across the network. Let's start our ...

  18. What is my port number and why does it matter for internet usage?

    Type in "Network Utility" and hit your Return key to launch the native Network Utility app. Select the very last tab, Port Scan. Enter the IP address you wish to scan for open ports. Your visible IP address can be found under the "Info" tab, or you can simply use the "127.0.0.1" localhost loopback IP.

  19. CompTIA A+ Rapid Review: Networking

    There are several port numbers you should know for the exam. They are: FTP (20 and 21), Telnet (23), SMTP (25), POP3 (110), IMAP (143), DNS (53), HTTP (80), HTTPS (443), and RDP (3389). ... You should know the primary purpose of the following protocols mentioned in this objective: DHCP. Assigns an IP address and other TCP/IP configuration to ...

  20. Ports for Network+, Security+, and SSCP Exams

    Well known port numbers are matched to specific protocols and when you see the port, you should be able to identify the protocol. Sometimes you may be given the protocol and be required to identify the port. There are 1024 well known TCP and UDP (numbered 0 through 1023) but you don't need to memorize them all.

  21. 14 common networking ports you should know

    In this example, -v stands to volume, and you should see outputs similar to this: debug1: Connecting to example.com [<IP Addr>] port 22. As shown, SSH is trying to connect to example.com uses port number 22. I may use an -p option the specify another port number; otherwise, SSH will default to 22.

  22. webserver

    23. A port number is a 16-bit unsigned integer, thus ranging from 0 to 65535 (although 0 cannot be used for TCP; it has a special meaning for UDP). You can use pretty much any port number in the range, however there are some guiding rules: (On Unix based systems at least), only root can bind to ports below 1024.

  23. How to find your port number

    Select "Advanced settings.". Click on "Inbound Rules" on the left. Click on "New Rule" on the right. Choose the "Port" option. Go to "Protocol and Ports.". Choose the protocol (TCP or UDP) and add the port number into the "Specific Local Ports" section. You can find the list here. Press "Next" and choose "Allow the ...

  24. How to port to Telkom in 2024: Full step-by-step guide on how to ...

    There is no online porting system yet. Instead, you should message PORTME#youridnumber#iccid to 081 160 7678. How can you port your mobile number online? There is no way to port your mobile number ...

  25. AT&T's network is having problems: What you should know while ...

    FILE _ A cellular phone tower is shown on Monday, May 22, 2017 in High Ridge, Mo. A number of Americans are dealing with cellular outages Thursday, Feb. 22, 2024, on AT&T, Cricket Wireless ...

  26. SOS symbol appears on iPhones during AT&T outage: What is it?

    Here's what to know. AT&T down: ... "When you make a call with SOS, your iPhone automatically calls the local emergency number and shares your location information with emergency services ...

  27. AT&T's network is having problems: What you should know while

    AT&T's network is having problems: What you should know while navigating a phone service outage. ... Aug. 20, 2023, in Kansas City, Mo. A number of Americans on Thursday, Feb. 22, 204, are dealing with cellular outages on AT&T, Cricket Wireless, Verizon, T-Mobile and other service providers, according to data from Downdetector. AT&T, who was ...

  28. After AT&T customers hit by widespread outage, carrier says service has

    As of 8 a.m. ET on Thursday, Downdetector had more than 60,000 reports of service issues from AT&T customers. Most of the complaints were focused on problems with their mobile phones or wireless ...