Are we telnet-ing to tcp port 22, or udp port 22?

When we do "telnet x.x.x.x 22", are we telnet-ing to tcp port 22, or udp port 22? Because SSH port 22 is both tcp and udp.
Thanks
Stro

Stro,
The telnet server/deamon will only listen to TCP port 23. A telnet client will only use TCP as the transport protocol. I guess you could write your own telnet client (or use netcat) to use UDP but on a Cisco router the telnet process will not respond unless the connection request comes in on TCP port 23. A quick search on the web reveals this question is asked alot, for what reason I am unsure. Here's a wiki article:
http://wiki.answers.com/Q/Why_should_telnet_to_UDP_ports_fail
Hope this helps,
Tim

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Unable to telnet on command prompt for udp port 514, but able to on cmd for tcp port 514

I am unable to telnet on command prompt for udp port 514. But when I use packet snifer or wireshark I am able to see traffic going to the targetted server from udp port 514. I thought it might be a firewall issue blocking the port from communicating. But
I figured out that windows firewall is disabled. I am able to make similar connections on the cmd for tcp port 514.
I did a netstat -an and see that udp:514 is enabled and listening on the server.
What am I missing here?

Telnet actually supports TCP only. You might want to try another tool as suggested here: http://serverfault.com/questions/263032/how-to-connect-to-a-udp-port-command-line
This posting is provided AS IS with no warranties or guarantees , and confers no rights.
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CTC TCP/UDP Ports numbers

Does anyone know the TCP/UDP Port numbers that have to be opened up when using NAT, this is what I have:
CTC PC >>>>>>>>>>> ROUTER >>>>>>>>>>>ONS15454
The CTC PC and the ONS are on different IP Networks so I'm the router to translate from one to the other with NAT, configured the ONS15454 to use Socks.
I used to have a document that explained this but I've lost it.
THanks
Chris

Hi Chris.
I see you already have provisioned the node for SOCKS Proxy. If you want to be able to still have IP connectivity (for ping or telnet) to the ENE's, then enable the SOCKS Proxy Only option. The SOCKS Proxy needs to be provisioned on the LAN connected 15454 at the very least. You can also go to the CTC drop down menu: Edit -> Preferences -> Firewall and change the port from being variable to static default. That will further restrict the ports that are used by CTC. This should resolve any intermittent connectivity issues in CTC if it is being caused by a firewall.
www.cisco.com/en/US/docs/optical/15000r9_1/15454/sonet/reference/guide/454a91_nwconnectivity.html#wp42216
"If you launch CTC against a node through a Network Address Translation (NAT) or Port Address Translation (PAT) router and that node does not have proxy enabled, your CTC session starts and initially appears to be fine. However, CTC never receives alarm updates and disconnects and reconnects every two minutes. If the proxy is accidentally disabled, it is still possible to enable the proxy during a reconnect cycle and recover your ability to manage the node, even through a NAT/PAT firewall."
Lastly, to answer your question directly below is a link to the list:
www.cisco.com/en/US/docs/optical/15000r9_1/15454/sonet/reference/guide/454a91_nwconnectivity.html#wp59962
Table 14-6 Ports Used by the TCC2/TCC2P
Thanks,
Will

TCP/UDP Ports and site used by FEP to download updates - needed to allow on perimeter firewall

Can some one point me with information like what TCP/UDP ports are utilized by FEP and what DNS / site Name it uses to download FEP Updates. This is needed to tighten perimeter FireWall policies
Thank you

It should be the same as the documentation for all Software Updates:
https://technet.microsoft.com/en-us/library/bcf8ed65-3bea-4bec-8bc5-22d9e54f5a6d#BKMK_ConfigureFirewalls
Make sure to expand the "restrict access to specific domains" section to see the update related URLs.

Should I block TCP/UDP ports 135 to 139 on my router?

For the sake of Internet and Desktop security should I block TCP/UDP ports 135 to 139 both ways at all times on my router? This seems to be recommended for Windows environments. Does Mavericks need these ports for its proper operation? When tested, ports 135, 137,18 show as closed whereas all other ports are Stealth. Ideally, they should all be Stealth.

Have a read here: http://securityspread.com/2013/07/26/firewall/
Stealth is just as good as closed, some would argue that stealth is just as much of a giveaway of the port being present as it being closed.
The specific ports you mention pose no risk to OS X as far as I am aware.

Does adding tcp udp ports on the nat exempt accesslist which is binded to nat 0 statement remove the entire nat 0 statement itself?

Hi Experts,
Is the above statement true?. I learnt later that adding tcp and udp ports on the nat 0 statements are supported . But does it take away the entire nat statement? Please answer my question at the earliest.
Regards
Krishna

Krishna,
"NAT exemption (nat 0 access-list command)—NAT exemption allows both translated and remote hosts to initiate connections. Like identity NAT, you do not limit translation for a host on specific interfaces; you must use NAT exemption for connections through all interfaces. However, NAT exemption does enable you to specify the real and destination addresses when determining the real addresses to translate (similar to policy NAT), so you have greater control using NAT exemption. However unlike policy NAT, NAT exemption does not consider the ports in the access list. NAT exemption also does not support connection settings, such as maximum TCP connections."
Reference
So, since the documentation clearly says that this rule does not consider any ports in the ACL, then one should not be testing unsupported configurations.
If one adds an ACL with specific ports, then unexpected results may be expected.
My suggestion, dont add any ACL entry with specific ports to your NAT exempt statement.
Thanks.
Portu.
Please rate any helpful posts

Our IT Director will not allow the appropriate TCP and UDP ports to be opened on the district WAN

I have about 30 Apple TV Units and our IT Director will not allow the appropriate TCP and UDP ports to be opened on the district WAN. When our teachers try to log on to Apple TV to broadcast lessons, websites, etc., they are booted off the network after about 20 minutes.
Any ideas for how I might solve this without having to hard-wire the Apple TV Units?

Honestly, you do not.
Either the IT director will cave and allow the appropriate ports or it doesn't work.
Hard wiring the ATVs will not rectify the problem.

QOS Network Planning - TCP/UDP Ports used in CWMS 2.5 MDC deployment

Does anyone know if there is documentation that describes the WAN traffic in CWMS 2.5 MDC? I'm looking for the TCP/UDP ports that must be prioritized on the WAN to properly class our traffic between the two data centers. I can't find any such document.
Thanks,
Matt

HI Matt,
All the network requirements are listed in the CWMS 2.5 Planning Guide in Networking Checklist: http://www.cisco.com/c/en/us/td/docs/collaboration/CWMS/2_5/Planning_Guide/Planning_Guide/Planning_Guide_chapter_0100.html
I hope this is what you are looking for.
-Dejan

TCP ports versus UDP ports

hi all i'm trying to understand the difference between connecting on TCP versus UDP ports.
My understanding is that you connect to TCP Ports like this
new Socket(server, port);
A TCP port scan would consist of trying to connect to ports 1 to 65536.
Is that correct ?
Now sending a message to UDP
try {
dsock=new DatagramSocket();
} catch (SocketException se) {
response="SocketException: " + se.toString();
try {
dsock.send(new DatagramPacket(message.getBytes(),
     message.getBytes().length,
          InetAddress.getByName(server),
          port)
} catch (UnknownHostException e) {
response+="UnknownHostException:" + e.toString();
} catch (IOException e) {
     response+="IOException: " + e.toString();
Would I also try to send the message on UDP with ports 1-65536
Stephen

Do you have
http://www.kohala.com/start/tcpipiv1.html
in your library? If not, get it.
In case you don't have time, however, there are basically five things that direct a packet: the source IP address, the source port, the protocol (e.g. TCP or UDP), the destination IP address, and the destination port.

TCP/UDP ports between Cisco PI 2.0 and WLC5508

Hello,
I will install Cisco PI 2.0 behind a firewall for security reason. The WLC5508 is before a firewall. Can anybody let me know which TCP/UDP ports need to be open specifically between the Cisco PI and WLC? I don't see that from the below link.
Cisco Prime Infrastructure 2.0 Quick Start Guide
http://www.cisco.com/c/en/us/td/docs/net_mgmt/prime/infrastructure/2-0/quickstart/guide/cpi_qsg.html#wp46865
Thanks,
Robert

Firewall Between the WCS and Controller or WCS and the WCS User Interface
When a PI server and a PI user interface are on different sides of a firewall, they cannot communicate unless these ports on the firewall are open to two-way traffic:
80 (for initial http)
69 (tftp)
162 (trap port)
443 (https)
Open these ports in order to configure your firewall to allow communications between a PI server and a PI user interface.
Regards
Dont forget to rate helpful posts

What TCP/UDP ports need to be open for VPN Client version 4.8?

What TCP/UDP ports need to be open for Cisco VPN Client version 4.8 to work?
Thanks,

Normally, you need the following ports and protocol :
UDP 500
UDP 4500
ESP
In case, you are using IPSec over TCP you have to open, TCP port 10000 or any other port you want to use for IPSec connections (Its configurable).
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Which TCP/UDP ports need to be opened on a firewall for adobe reader and flashplayer?

Which TCP/UDP ports need to be opened on a firewall for adobe reader and flashplaer to operate properly? This would include updating, linking, and any subset of features.

The Acrobat Family uses TCP HTTP/HTTPS for all traffic. The following processes and ports may be active on a Windows client machine:
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Acrobat.exe - links in documents - anything specified in the URL
AdobeCollabSync.exe - Tracker review data - port 443
The same ports are used by the program components on OS X.
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I have a Macbook Pro 13.3 i5 w/ no hdmi port. How can I connect my Mac to TV to watch video, photo ? Is the Thunderbolt port a mini display port where I can use a mini display port to HDMI cable? If not, what are my options??

I have a Macbook pro 13.3 w/ i5 that has no hdmi port. I want to be able to connect the Mac to my TV set to watch Video, Photos and files from Mac to TV.
Is the Thunderbolt port similar to a display port or mini display port? Can I use thunderbolt port to connect thru a mini displayport to HDMI cable or converter?
Been trying to locate a USB to HDMI cable or converter (at a reasonable price) but all I found is a displayport or mini displayport to HDMI cable/converter.
What other options are available ?
Thanks a lot for your assistance.

Thunderbolt uses a Mini DisplayPort adapter to send video and audio to HDMI. Here's some on Amazon http://www.amazon.com/s/ref=nb_sb_ss_c_2_8?url=search-alias%3Dcomputers&field-ke ywords=mini+displayport+to+hdmi&sprefix=mini+dis%2Caps%2C249#/ref=nb_sb_noss?ur l =search-alias%3Dcomputers&field-keywords=mini+displayport+to+hdmi+with+audio&rh = n%3A172282%2Cn%3A!493964%2Cn%3A541966%2Ck%3Amini+displayport+to+hdmi+with+audio

Anybody know what tcp or udp port # is used by Server Monitor?

Hi everyone. I've been lookin' all over ****'s half-acre to find out what port # is required for Server Monitor with no luck. Sure, I can access the local IP address on the LAN, but for LOM to be truly useful...I need to access from WAN. Since my public IP takes me direct to the server itself (and other ports on that ip do other things), I really need to know what port # is used to forward Server Monitor traffic. Anyone?
Thanks!
Ed

Ed LaComb-
I do have this link to well known TCP and UDP ports used by Apple software products.
I am fairly certain the answer lies within.
Luck-
-DaddyPaycheck

HT4814 TCP and UDP ports on router firewall to allow server to server administration running mavericks and server app 3.0?

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Also you may want to open tcp port 625 so that you can update the server's OD master.
More info can be found here: http://support.apple.com/kb/ts1629 Well known TCP/UDP ports used by Apple Products.
HTH
- Leland

Are we telnet-ing to tcp port 22, or udp port 22?

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