[asterisk-users] Moving from DSL to T1

[Gordon Henderson]

On Sun, 12 Sep 2010, Kevin Keane wrote:

> -----Original Message-----
> From: asterisk-users-bounces at lists.digium.com [mailto:asterisk-users-bounces at lists.digium.com] On Behalf Of Steve Edwards
> Sent: Sunday, September 12, 2010 5:57 PM
> To: Asterisk Users Mailing List - Non-Commercial Discussion
> Subject: Re: [asterisk-users] Moving from DSL to T1
>
> On Sun, 12 Sep 2010, Kevin Keane wrote:
>
>> What really matters is the latency, and T-1 is a huge improvement over
>> DSL in that area. The easiest way to measure latency is the ping time
>> to a server that is ?close to you? Internet-wise. A DSL has latencies
>> of between 40ms (if it?s extremely good and not too many other people
>> are using it) and 1000ms (if there is a problem somewhere). A good T-1
>> may have latencies as low as 5 ms or so. Also, with a T-1 the
>> bandwidth is guaranteed and bidirectional. With a DSL line, you may
>> get burstable bandwidth ? you don?t actually have that bandwidth, you
>> just get to compete for excess bandwidth with your neighbors.
>
>> You are confusing DSL with cable.
>
> Both, actually. The latency numbers are actual numbers measured at a customer site.

Ouch.

My home/office ADSL connection (8Mb in/832Kb out) - ping to my external 
default route:

   $ ping -q -c10 188.39.1.26
   PING 188.39.1.26 (188.39.1.26) 56(84) bytes of data.

   --- 188.39.1.26 ping statistics ---
   10 packets transmitted, 10 received, 0% packet loss, time 9008ms
   rtt min/avg/max/mdev = 12.913/13.266/13.747/0.286 ms

Ping to one of my hosted servers:

   $ ping -q -c10 unicorn.drogon.net
   PING unicorn.drogon.net (195.10.225.68) 56(84) bytes of data.

   --- unicorn.drogon.net ping statistics ---
   10 packets transmitted, 10 received, 0% packet loss, time 9009ms
   rtt min/avg/max/mdev = 17.801/18.443/19.994/0.610 ms

If 40ms is when it's extremely good, then I'm glad I don't live where you 
are!

(However you're right about leased lines, E1 where I am is typically 
2ms-3ms, but people here are moving to Ethernet based carriers now)

Gordon