EIGRP Port Number

[edsantos1]

BGP uses port 179 to transfers but what port does EIGRP use??

[pkhatri]

Hi,

BGP uses TCP which is why it has a port number. EIGRP runs directly over IP using IP protoco number 88 - it does not use TCP or UDP.

Hope that helps - pls rate the post if it does.

Paresh

[edsantos1]

Thanks,

Is there a document or site somewhere that explains this in more detail?? I'm intrigued to know how EIGRP communicates with its neighbors.

Thanks

Ed

[pkhatri]

Hi Ed,

You might wanna read this document for starters:

http://www.cisco.com/en/US/customer/tech/tk365/technologies_tech_note09186a0080093f07.shtml

Also, there's a whole host of EIGRP docs here:

http://www.cisco.com/en/US/customer/tech/tk365/tk207/tsd_technology_support_sub-protocol_home.html

Pls remember to rate posts.

Paresh

[ruwhite]

While EIGRP does run directly on top of IP, port 88, it also uses a port number, believe it or not.... :-) The port number is the EIGRP AS. That's how EIGRP neighbors know not to form a neighbor relationship with adjacent routers that aren't in their AS--they won't even receive the packets sent by a router in another AS!

http://www.cisco.com/en/US/customer/tech/tk365/technologies_white_paper09186a0080094cb7.shtml

Is the more complete one, and more recent.

HTH.

:-)

Russ.W

[bhedlund]

What Russ hasn't mentioned here is that he has written a fantastic article on EIGRP in the latest edition of Packet Magazine.

I encrourage everyone to read it:

http://www.cisco.com/web/about/ac123/ac114/ac173/Q1-06/p_15.html

Thanks Russ.

Respectfully,

Brad