high density of analog under ip telephony solution

nkariyawasam · ‎02-21-2008

I have a customer requiring large number of analog phone connectivity with IP Phones, and it is a multi site implementation . each site requires mixture of both ip phones and analog phones.

For example, main site needs some 200 ip phones and 800 analog phoenes. Branche would need 5 ip phones and 25 analog phones.

While IP enabled hybrid PBX (non-Cisco) can cater for this requirement, what is the Cisco's option that we can have for this ?

Rob Huffman · ‎02-22-2008

Hi Nalaka,

Excellent question here! We use a number of VG248's that supply 48 Analog ports per device, and really like the product.The VG248's are really great to install and they ship with an excellent step by step guide. Have a look at these docs that explain the Hardware and Software components of the install;

Cisco VG248 Analog Phone Gateway

http://www.cisco.com/en/US/products/hw/gatecont/ps2250/products_data_sheet09186a008007c9bb.html

Installing the VG248

http://www.cisco.com/en/US/products/hw/gatecont/ps2250/products_installation_guide_chapter09186a00800878f4.html

VG248 Software Configuration Guide v1.3

http://www.cisco.com/en/US/products/hw/gatecont/ps2250/products_configuration_guide_chapter09186a008023514f.html

The way that they "wire out" with RJ21 25 pair cables really fits nicely into most wiring infrastructures.

You can order most any length of pre-made 25pr cable that will connect to the Front Panel of the VG248 and can be routed right to the existing cross-connect (punch down blocks) or you can terminate (on punch down blocks, Bix,110 Blocks,R266) the VG248 25 pr cables in a Central location and run a new Tie Cable or Cables to the existing cross-connect. The "old" Analog circuits can be traced and new connctions to the VG248 can easily replace them pair for pair, circuit for circuit. This is nice for a "phased" approach :)

We have migrated hundreds of Analog lines from Nortel to the VG248 in just this manner. Using the type of cable listed below;

Cisco RJ21 Cables

http://www.stonewallcable.com/product.asp?dept%5Fid=102&pf%5Fid=SC%2D9754

Hope this makes sense! We have about 6 new VG's to install here in the next few months :)

Rob

pcameron · ‎02-22-2008

The VG248 is getting towards the end of the product's life. The replacement for it would be the VG224. This gives 24 analogue FXS lines under SCCP, MGCP or H323 control and has the advantage of using later model DSP's and is also configurable using IOS. It would proabably be the device of choice for new installations now. It uses the same cable connector that Rob has detailed, so it is quite easy to integrate with legacy PBX cabling.

Rob Huffman · ‎02-22-2008

Hi Paul,

First off, Thanks for your participation here. It really helps when great people get involved in these discussions!

As always, a product we really love is getting replaced (bummer!) When will this be announced or am I just "asleep at the wheel" on this one.

I have not seen an EOS/EOL notice for the VG248;

http://www.cisco.com/en/US/products/hw/tsd_products_support_end-of-sale_and_end-of-life_products_list.html

Or here;

http://www.cisco.com/en/US/customer/products/prod_end_of_life.html

Please let me know what I'm missing here :)

Thanks,

Rob

pcameron · ‎02-22-2008

The V248 is an aging product that is in sustaining mode, meaning there is no new development expected for the device. The DSP's it uses are not capable of providing many of the more advanced features that are coming out for other platforms.

There has not been any EOS date determined just yet, but the general recommendation for high density FXS gateways would be the VG224 as it offers a greater range of current features and has much more scope for enahancements in the future.

If you love the VG248, you've been doing this job for too long :-)

Rob Huffman · ‎02-22-2008

You've got that right Paul :) Thanks for clearing this up for me my friend! 5 points for this from Calgary.

Take care,

Rob

nkariyawasam · ‎02-22-2008

Hi,

Not only FXS ports, but costomer has existing Lots of CO lines at the branch levels ( of course, they want to retain those telephone numnbers) and many branches having 30 odd CO lines. Only option is to use HDA cards on router in this case I bilieve, But support 30 FXO is really challanging.

Any ideas ?

chris.mann · ‎02-22-2008

PRI/T1/E1 for incoming voice should replace your 30 current analog POTS lines just fine. Unless you're in a situation where for some reason that isn't an option.

In addition to the vg224 option, there are also some 24 port modules for CMM cards. I have several WAN deployed sites, and use both solutions depending on the other hardware onsite.

nkariyawasam · ‎02-23-2008

This case the analog CO lines cannot be changed to E1 because of;

1. The telephone numbers being used for long time and customer do not want to change those ( when they switch over to E1, there wil be new set of numbers).

2. Some remote areas, E1 features are not available with service provider due the limitations of the telephone exchanges.

What are the options available for high density of FXO interfaces ?