So, as you can see in Figure 5, my device has TCP ports 21, 23, 53, 80 and 5555 open. Nmap, in this mode, has scanned a total of 1,000 ports. Figure 5. Using nmap to perform port scanning at 192.168.1.1 (router’s IP)

TCP port 21 — FTP (File Transfer Protocol) TCP port 22 — SSH (Secure Shell) TCP port 23 — Telnet. TCP port 25 — SMTP (Simple Mail Transfer Protocol) TCP and UDP port 53 — DNS (Domain Name System) Jul 23, 2012 · 5. Filter by Protocol. Its very easy to apply filter for a particular protocol. Just write the name of that protocol in the filter tab and hit enter. In the example below we tried to filter the results for http protocol using this filter: http 6. Using OR Condition in Filter Nov 05, 2014 · then we are able to do post analysis, for example using both previous commands. tcpdump -i eth0 udp port 53 -w example.cap. then we may read back from the file. tcpdump -v -r example.cap udp port 53 Detailed description and additional information. Here I’m providing a closer look. It’s not a matter of receiving and transmitting data. TCP is bidirectional; you establish a TCP connection, generally to a well known destination port number from a randomly chosen unused source port number.

Mar 29, 2020 · SMB uses either IP port 139 or 445. Port 139: SMB originally ran on top of NetBIOS using port 139. NetBIOS is an older transport layer that allows Windows computers to talk to each other on the same network. Port 445: Later versions of SMB (after Windows 2000) began to use port 445 on top of a TCP stack. Using TCP allows SMB to work over the

Oct 31, 2009 · DNS uses UDP for DNS Queries over Port: 53. A client computer will always send a DNS Query using UDP Protocol over Port 53. If a client computer does not get response from a DNS Server, it must re-transmit the DNS Query using the TCP after 3-5 seconds of interval. Jan 31, 2020 · In the Internet Protocol version 4 (IPv4) there is a field called "Protocol" to identify the next level protocol. This is an 8 bit field. This is an 8 bit field. In Internet Protocol version 6 (IPv6) [ RFC8200 ], this field is called the "Next Header" field.

Introduction. This article provides an overview of ports that are used by Citrix components and must be considered as part of Virtual Computing architecture, especially if communication traffic traverses network components such as firewalls or proxy servers where ports must be opened to ensure communication flow..

TCP port 53 can be used in the cases where the DNS responses greater than 512 bytes. However, using UDP messages are preferable to using TCP for large DNS messages is due to the fact that TCP Additionally, if Internet Protocol security (IPsec) is deployed in your organization, IPsec must be disabled over the range of ports used for the delivery of audio, video, and panorama video. While this may seem a bit daunting at first, the heavy lifting for planning this can be done using the Skype for Business Server 2015 Planning Tool. Once This is a list of the IP protocol numbers found in the field Protocol of the IPv4 header and the field Next Header of the IPv6 header. It is an identifier for the encapsulated protocol and determines the layout of the data that immediately follows the header. Both fields are eight bits wide. Using Telnet to Test Open Ports. One of the biggest perks of Telnet is with a simple command you can test whether a port is open. Issuing the Telnet command telnet [domainname or ip] [port] will allow you to test connectivity to a remote host on the given port. Issue the following command in the Command Prompt: telnet [domain name or ip] [port] HTTP (port 80) (Note: Not applicable to Ring Alarm Base Station) HTTPS (port 443) DNS (port 53) NTP (port 123) These are well-known ports and it is unlikely that your device will have trouble accessing them. In addition to the ports above, your Ring device makes several other types of connections. Protocol. TCP/UDP. Port Number. Description. File Transfer Protocol (FTP) (RFC 959) TCP. 20/21. FTP is one of the most commonly used file transfer protocols on the Internet and within private networks. An FTP server can easily be set up with little networking knowledge and provides the ability to easily relocate files from one system to another. As we witnessed with the dhcpserver port on Felix, certain open UDP services can hide even from Nmap version detection. He has also only scanned the default ports so far, there are 64529 others that could possibly be open. For the record, 53 is the only open UDP port on Scanme.