On Thu, 10 Apr 1997, Curt Eckhart wrote:
> I haven't been tuned into the list for about two months now, and I
> need to get back up to speed. Could someone succinctly explain how
> may dialup ports of what type can be supported in a "filled-up" PM3
> and what kind (and how many) of PRI/T1 lines it takes to support it ?
In USA T1/PRI is available. E1 is European etc... so we won't talk about
this.
Channelized T1 is a T1 connection that has 24 channels for calls ...
imagine 24 POTS on one.
PRI also has 24 channels but for now the PM3 uses 1 channel as data
signalling, the D-channel, so that leaves you with 23 channels for
calls...
PM3s come in 4 flavors that we're concerned with here.
PM-3A-1T AC powersupply 1 PRI/T1 connection
PM-3D-1T same as above but with DC powersupply for colocation in Telco
facility
PM-3A-2T Like 1T but can take 2 PRI/T1
PM-3D-2T ditto...
so on the x-1Ts you can have a T1 or a PRI for 24 or 23 channels.
the x-2Ts you can have 48 or 46.
Just the chassis alone (no modem cards) you can do ISDN connections one
per channel (unless bonding channels), well kinda, the PRI is a guarantee
(PRI is an ISDN type signal if that's the right term). I'm not sure about
the Channelized T1, but someone here will give the information...
Now if you want a channel to do an analog connection or 56K connect, THEN
you need modem cards. The modem cards are hot swappable and the Lucent
based chipset is expected in June, but that's a guesstimate. There are
two versions of the cards the 8- and 10-port modem cards. These are also
intelligent in that if you have extra ports available, then these are
pulled into use and the bad port is taken out of service.
My recommendation is to have at least 2 extra ports JIC. So we've
requested 4 10-port cards adn 1 8-port card for a 2 PRI setup. Again 2
PRI = 46 channels equivalent to 46 POTS, so we have 2 ports as backup.
> If this a mix-n-match sort of thing (i.e. if you get more digital
> modems, you get less of something else), could you please explain this
> to me too ?
It depends on how you provision with the telco...we've decided to not
offer ISDN service so our PRIs are voice aka analog only for billing.
Thus we need the requisite modem cards. If you were to mix-n-match then
you'd want to tailor the mix to your expected ratio. say 1 PRI for ISDN
and 1 PRI for analog. Then you'd probably go with 3 8-port modem cards...
Note: get total pricing for PRI and Channelized T1 first from your telco
to see which may be more appropriate, in some instances POTS is still
cheaper.
> I'm about to make the jump to digital and I need to understand this
> more than I do.
Good for you! Contact sales@livingston.com, tell them your telco and
hopefully they'll have the buzzwords you can say to the telco to get setup
properly the first time. Again, check pricing!! and determine what you
will be offering (ISDN and Analog, Analog only, Future plans for K56Flex)
all of this will figure in to what will be effective for you.
> P.S. I've been to the Web site, but I still haven't found the plain
> english explanation there if there is one.
It's hard to balance the information there in layman's terms as each telco
seems to have their own lil buzzwords...
e-mail me private if you have further information dug up and have
questions about it. or again contact sales@livingston.com (bug Mike
Mann... ;)
-- Aloha,Sherwood