Speeds and feeds

tqbf@pobox.com tqbf@pobox.com
Wed, 3 Jun 1998 17:01:20 -0500 (CDT)

> (or copper) and channelize the T-3 for maybe 10Mpbs of the 45Mbps
> available.  However money is money, T-3s take time, a Cisco 7000 is
> about $20K, the CT3IP card is about $50K, so multiple T-1s are still in
> the running.

Why on Earth would you buy a channelized DS3 card when the only thing
you're using the DS3 for is Internet connectivity? If you are only going
to use a fraction of the available bandwidth of the link, and you must
have a DS3, negotiate a contract with your provider for a bandwidth-capped
DS3. DON'T simulate one with an expensive channelized DS3 card. Get a HSSI
port and some D-Link termination equipment (or whatever's cheapest).

The purpose of those cards is to allow you to break a T3 into multiple
DS1s, and that's really just attractive when you need lots of DS1s (ie, if
you're an Internet service provider and you want to sell tens of DS1's out
of a single card).

> I would rather use redundant feeds and BGP, but migrating from set ISP
> IPs to a BGP A.S. is...intrusive.  (Thinking to myself: Hmm, would also

And, if you only have 1 class C, not likely. Obtaining an ASN isn't hard,
assuming you have more than one provider, but getting enough IPs so that
you can announce the minimum-sized block via BGP is extremely difficult.

> A completely separate T-1 and firewall is the path of least resistance,
> but isn't a balanced use of bandwidth.

Why isn't a seperate DS1 "balanced"? 

Thomas H. Ptacek	  The Company Formerly Known As Secure Networks, Inc.
http://www.pobox.com/~tqbf	 "If you're so special, why aren't you dead?"