RE: Mac access-list protocol list on Univercd?

From: Paul Dardinski (pauld@marshallcomm.com)
Date: Sat Jun 24 2006 - 09:59:55 ART

I was referencing vlan access-maps, specifically trying to allow
required layer 2/3 protocols across, while dropping all else. I am just
trying to make sure that if doing an access-map and using a "drop" at
the end, I allow required protos before this. I know that if I only
allow IP across for example, I end up with blocking ARP and STP (at
minimum) at the end. Just trying to avoid this trap.....

  _____

From: petrsoft@gmail.com [mailto:petrsoft@gmail.com] On Behalf Of Petr
Lapukhov
Sent: Saturday, June 24, 2006 8:54 AM
To: Paul Dardinski
Cc: Cisco certification
Subject: Re: Mac access-list protocol list on Univercd?

Paul,

please do not confuse LSAP values with Ethertypes.
They are from different Ethernet frames format :)

Ethertype 0x4242 has nothing to do with LSAP 0x42 :)

Check this link for more details on four ethernet frame types:

http://www.wildpackets.com/support/compendium/ethernet/frame_formats

 --
Petr Lapukhov, CCIE #16379
petr@internetworkexpert.com

Internetwork Expert, Inc.
http://www.InternetworkExpert.com
Toll Free: 877-224-8987
Outside US: 775-826-4344

2006/6/24, Paul Dardinski <pauld@marshallcomm.com>:

Thanks Peter. The listing shows IEEE STP (4242) as "PCS Basic Block
Control".....who knew...just need to memorize STP/ARP I hope:-)

  _____

From: petrsoft@gmail.com [mailto:petrsoft@gmail.com] On Behalf Of Petr
Lapukhov
Sent: Saturday, June 24, 2006 8:38 AM
To: Paul Dardinski
Cc: Cisco certification
Subject: Re: Mac access-list protocol list on Univercd?

A good reference of Ethertypes:

http://www.cisco.com/univercd/cc/td/doc/product/software/ios124/124cr/hb
r_r/br_aph.htm

[IOS Bridging Command Reference Appendix]

As for LSAP values, I don't know of a good link in DocCD. I usually use
this one
in real life:

http://www.cisco.com/warp/public/473/111_12.html

It's not hard to remember some major ones, notably IEEE STP and SNAP :)
(PVST+ aka SSTP uses SNAP encapsulation. Go figure ;)

I don't think we need anything else nowdays, though who knows for sure
;)

HTH 

--
Petr Lapukhov, CCIE #16379
petr@internetworkexpert.com

Internetwork Expert, Inc.
http://www.InternetworkExpert.com
Toll Free: 877-224-8987
Outside US: 775-826-4344

2006/6/24, Paul Dardinski <pauld@marshallcomm.com>:

Does anyone know if there any listing of protocols for use in mac acl's
anywhere on the univercd? Specifically, ARP/STP, etc? I seem to keep
tripping up over this as there are many layer 2 protocols that each have
their own matching id's.

Thanks,

PD

This archive was generated by hypermail 2.1.4 : Sat Jul 01 2006 - 07:57:33 ART