[162466] in North American Network Operators' Group
RE: Cross country point to point link question
daemon@ATHENA.MIT.EDU (Vinny_Abello@Dell.com)
Thu Apr 18 13:35:14 2013
From: <Vinny_Abello@Dell.com>
To: <Petter.Bruland@allegiantair.com>, <nanog@nanog.org>
Date: Thu, 18 Apr 2013 17:34:45 +0000
In-Reply-To: <DC864220297BE047821E58CF67B23F6E6C03BAF8@SVIEXCMB01.allegiantair.com>
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
Assuming you're doing FCoE or just iSCSI, you REALLY need to make sure your=
SAN vendor blesses something messing with packet headers on the SAN traffi=
c. I don't think the caching mechanisms on the typical accelerator would he=
lp at all either. I somehow doubt they would support that unless they have =
their own solution.=20
If you're just doing SMB or NFS or something similar then yes it would prob=
ably help overcome performance issues tied to latency quite a bit. But agai=
n, the magic is usually all tied to compression, TCP header modification an=
d caching algorithms to local storage on each device.
-Vinny
-----Original Message-----
From: Petter Bruland [mailto:Petter.Bruland@allegiantair.com]=20
Sent: Thursday, April 18, 2013 12:20 PM
To: nanog@nanog.org
Subject: Cross country point to point link question
Question for someone with some experience with long haul links (Las Vegas -=
- New Jersey)
[Cisco 4510 - SVI-VLAN x]---trunk---[Nexus5K LH optic]=3D=3D=3Dfiber=3D=3D=
=3D{carriers across country}=3D=3D=3Dfiber=3D=3D=3D[Nexus5K LH optic]---tru=
nk---[Cisco 4510 - SVI-VLAN x]
We have two circuits, one that is the same vendor from east to west, and th=
e other circuit is a two vendor deal. Both circuits are 1 Gbps with around =
67-70 ms delay.
As soon as we had the links turned up, our SAN guy started complaining abou=
t poor throughput, asking us to throw in a couple of wan accelerators.
He was seeing a max throughput of around ~200 Mbps.
Question: For a long haul 1 Gbps link with 67-70 ms delay, would installin=
g a pair of wan accelerators make a big difference?=20
Thanks,
-Petter Bruland
