* USR doesn't seem to believe in putting prices on their web. Wonder
why... Also, they don't even seem to believe in putting *product
info* online in a usable form. All of the product data sheets I
needed were available ONLY in PDF format. On top of that, they
weren't even in browsable PDF - they were available in "windows" and
"macintosh" formats - ie ZIPped and Binhexed. I had to download the
the windows version and unzip it on my UNIX box. And *then* the PDFs
have errors so I had to print them one page at a time, it errored out
Adobe's viewer if you tried to print all at once. Why do they make it
so hard?
* If you use the USR PRI solution you need to buy the TC rack, the
Dual PRI Card, the NETServer PRI Card, and the Quad Modem Card. It is
a mix and match setup. Needless to say the physical size is MUCH
larger than the PM-3. It isn't what I would consider suitable for a
POP, it is really good only for a central site. Which you can also do
with stacked PM-3s, so the size isn't an advantage. Personally I
think the stacked unit approach is better, but that is a religious
war.
* Going by their docs you also need the Network Management Card and
Total control manager. More stuff to buy. I can't compare price as,
again, they don't seem to put that up anywhere.
* The basic feature set sounds oddly like ComOS 3.1.4s features - not
surprising as we licensed them ComOS up to 3.1.4. But I don't see
later features listed - no listing of RFC 1877 DNS in PPP for
instance, yet the list just about everything PPP does. (Wow, PPP does
IP address negotiation and assignment?! Give me a break, why did they
list that stuff...)
* We support more switch types - USR does AT&T 4ESS, AT&T 5ESS,
Northern Telecom DMS-100 Standard, and Northern Telecom DMS-250. We
do AT&T 4ESS, AT&T 5ESS, DMS-100, ESWD, Net5, VN2, VN3, VN4, 1TR6,
NTT, and KDD.
* They support D4 or ESF frame formats - we do D4, ESF, CRC4, or FAS.
* They support B8ZS line coding - we do AMI, B8ZS, or HDB3.
* They support ITU-T Q.921, Q.931, and I.451 - we do I.431, Q.921,
Q.930, Q.931
* To be fair they do both V.110 and V.120 Rate Adaptation, we do V.120
* They don't do T1/Frac-T1/Channelized-T1 leased lines for PPP or
Frame Relay. That would be yet another card for the TC. It is built
into the PM-3.
* Both units have built in CSU/DSUs.
* Quote "10 PRI spans or 240 simultaneous users within a single
chassis." <http://www.usr.com/business/30422.html> Now on the PDF it
says "10 PRI spans, servicing up to 230 simlutaneous callers."
Ok... but the illustration shows 18 slots on the rack. So, 1 for a
dual PRI card, 1 for the NETServer PRI Card, one for the Network
Management Card. That leaves 14 slots. The modem cards are 4 modems
each, so that is 56 modems maximum. 8 more than you need - unless you
are in Europe, then you need 60. (Actually, it isn't clear if that
18th slot is a real slot, it is wider than the rest, maybe the power
supply or something. Any one with USR experience have the answer?) So
it looks like they are talking about an ISDN only solution with the
230. If you want full modem population you basically fill a chassis -
which means that you end up with more space used, more cards, more
power draw, and more heat to get the same basic support as a PM-3 -
without as many features. (And I strongly suspect more cost.)
* I see no mention of Multi-chassis multi-link PPP.
Data from these pages and the PDF files there:
<http://www.usr.com/business/30409.html>
<http://www.usr.com/business/30422.html>
<http://www.usr.com/business/30425.html>
<http://www.usr.com/business/30412.html>
<http://www.usr.com/business/30424.html>
<http://www.usr.com/business/30426.html>
<http://www.usr.com/business/30411.html>