09-08-2004 07:21 AM - edited 03-02-2019 06:19 PM
I'm looking at a application that is to support a large number of dial in users, each will make a short duration call. The number of concurrent users is quite low, and can be supported on 4 ISDN primary rate interfaces. I will use ISDN at the core with onboard modems in the AS, the users are using analogue modems.
The part I'm not so sure about is the best way to handle potentially 1000's of individual users. Im comfortable with dialer profiles and individual username and passwords using CHAP, but I dont think that will scale well to this type of application.
I've been reading up on virtual profiles based on templates, and also about supporting this using ACS for the AAA support, but haven't found any referencies or examples that pull all of this together.
Has anyone any thoughts on a possible way forward to meet this application?
09-09-2004 07:05 AM
Regarding the choice of platform (if not yet decided): as5350 with 4 port PRI & 2 x NP108 should work well.
Regarding configuration on the AS, have a few questions:
1. How many calls per seconds are expected?
2. What is the expected Ave hold time (users to remain online)?
3. What is the application we are aiming for? A point-of-sale (PoS) like application where the connection time should be fast but we do not need very high connect speeds (since the amount of data transferred is going to be very less) or we are expecting high data through put on each call (high data transfer)
Since we have 1000s of users, an external AAA server is advisable. Again depending upon the application we can use virtual profiles (with pre cloning) or can even terminate the calls on the group-async interface too.
Thanks, Mak
09-10-2004 05:38 AM
Hi Mak,
I'm looking at 80 concurrent calls, each having a duration of about 15 seconds from a POS terminal with a built in Modem.
If I was configuring this with dialer profiles on a router then I'd use one profile per user, but in this case I dont see that this is a viable approach.
After reading up on virtual profiles I think that I would end up with one VP per ISDN channel, say 120 for 4 ISDN 30 circuits, each VP cloned from a template. Then I use the AAA server to authenticate the individual user and provide unique details such as IP address, an ACL enrty and a route if needed.
Do you have any documents with examples I can read that show how to integrate the AS and the ACS systems. I've found several that refer to each component as an individual entity, but none that show the complete system.
Andy
09-10-2004 12:48 PM
If I understand your requirement correctly, you "should" have no problems using one of the AS5XXX products in this capacity. You would have something like this...
POS terminal----async dialup------AS-----IP------TCP transaction server
where ascii character data is encapsulated into tcp and forwarded to the proper ip address on the IP segment of the network. Your line configuration should look something like this.
line x y
no exec-banner
no flush-at-activation
no vacant-message
modem inout
autocommand telnet x.x.x.x yyy [ip and port of transaction server]
escape-character NONE
This should not require any special software or hardware, but more configuration trial and error to fit the specifics of your network.
Another way is:
If the PoS application requires speeds of 2400 or less, anything above that adds considerable time to the handshake. The protocol we need here is
V.22bis, with MNP, flow control, error correction, and data compression turned off.
You will need to create a modem init string or modemcap. This modemcap is globally defined and applied to the TTY lines. You will need the AT command set for your particular modems (NEXTPORT or MICA)
http://www.cisco.com/univercd/cc/td/doc/product/access/acs_serv/as5400/sw_conf/atnextpt.htm
The following is an example to limit connect speed to 9600 on NEXTPORT (AS5350/AS5400) modems.
modemcap entry POS misc &fs29=2s30=9600s31=9600
line x y
modem autoconfigure type POS
09-10-2004 01:10 PM
I think we should be fine by terminating the calls on the physical async interface itself (interface group-asyn x) & assigning ip address either through AAA or locally from the AS, per-user ACL & route can be downloaded from the AAA server.
http://www.cisco.com/en/US/tech/tk583/tk547/technologies_configuration_example09186a00800fa54a.shtml
Thanks, Mak
09-13-2004 06:16 AM
Thanks for that, I'll have a read through the information. I'm still trying to get hold of some kit, am planning a lab trial first.
Andy
10-18-2004 03:49 AM
Mak,
Well its taken some time, I've now got the kit and am planning to start the trial later this week. I'll no doubt be in touch!
Andy
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