Skip site navigation (1)Skip section navigation (2)
Date:      Wed, 17 Jan 2001 16:57:07 -0500
From:      Carroll Kong <damascus@home.com>
To:        Mike Tancsa <mike@sentex.net>
Cc:        freebsd-atm@FreeBSD.ORG
Subject:   Re: en performance/configuration.. WOW!
Message-ID:  <4.2.2.20010117164809.00c78ec0@netmail.home.com>
In-Reply-To: <5.0.1.4.0.20010117134944.01f3b890@marble.sentex.ca>

next in thread | previous in thread | raw e-mail | index | archive | help

>On the other end, my upstream has
>
>interface ATM1/0/0.14 multipoint
>   description - Sentex ATM
>   ip address 192.168.1.1 255.255.255.252
>   no ip directed-broadcast
>   no ip mroute-cache
>   map-group atm
>   atm pvc 15 0 130 aal5snap 35000 35000 inarp
>
>And the local Cisco 4700 has
>
>Interface ATM0
>  description Sentex ATM
>  ip address 192.168.1.2 255.255.255.252
>  atm pvc 1 0 130 aal5snap 35000 35000 inarp
>  map-group atm
>.
>.
>map-list
>  ip 192.168.1.2 atm-vc 1
>  ip 192.168.1.1 atm-vc 1
>
>
>I need to replace the Cisco 4700 with the FreeBSD box (I have a SM to MM 
>m/c to do the fibre conversion).  However, being an ATM novice, I am not 
>sure how to translate the above config into a FreeBSD config. On the 
>Cisco, I have
>atm pvc vcd vpi 130 rates rates ... and then inarp... If they are using 
>inverse arp, how does this affect my configuration. Do I need to use the 
>harp stack instead ? I am not sure how the inarp figures into this.
>On the two machines I have here, I did as the man pages suggested to bring 
>the back to back config up, and that worked... But I am not sure if the 
>above config only effects arp timeouts or works with an arp server somehow ?
>
>Any suggestions / tips would be much appreciated!
>
>
>         ---Mike

I am somewhat an amateur in ATM as well but I know a few things and I have 
worked on some Cisco boxes.  Looks like the Cisco 4700 is calling a 
maplist, on VP 0, VC 130.  Using aal5snap, with some projected 
bitrate.  Inverse ARP seems like an automated way to map IP addresses to 
PVCs.  See, normally in ethernet that is done for us with ARP since 
ethernet has a MAC address that maps back to an IP.  With ATM, there is no 
such animal (short of other methods, but for simplicity, I will not mention 
them).  So ATM needs a way to map back, and it is usually done with some 
static map listing IPs -> PVCs or in Cisco's case, Inverse ARP protocol.

You only need an ARP Server if you are using SVCs.  (IIRC... and/or 
LANE).  I think the Inverse ARP Protocol helps alleviate people who 
normally have to do some kind of static mapping between IPs and PVCs.

Could you send me privately your Cisco 4700's config?  Please omit any 
logins or enable passwds sequences.  Just curious on your overall setup and 
I might be able to figure some more out.  (so omit enable lines, and passwd 
lines on your console or other lines).

I am fairly certain that syntax is deprecated and replaced with newer lines 
if you have a more recent version of Cisco IOS.

As to how to configure the FreeBSD box to emulate this.  I am not quite 
sure.  I suppose you can statically define the IP to PVC mapping.  And ask 
the other end to do so as well since it will no longer have Inverse ARP 
protocol to rely on.  But I get a feeling they already have done the static 
map, and Inverse Arp is being redundant now.

-Carroll Kong



To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-atm" in the body of the message




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?4.2.2.20010117164809.00c78ec0>