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What VOIP Routers / firewalls should I use?

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kirboy

IS-IT--Management
Feb 2, 2002
7
GB
We have a working VOIP install for 3 seperate remote workers who are connected to our IP403. they are connected through VPN tunnels (IPSEC) across ADSL. The routers we are using are the Vigor 2600 range from draytek. The problem we have (as you would expect) is the quality of the calls. As sson as web browsing, file transfer, RDP etc occurs at the same time as a call the voice quality is greatly affected.

Do you know of any Routers / Firewalls that you have used for the same scenario that can do QOS and give good results for voice traffic accross ADSL.

 
You haven't said what you are using as the IP Endpoints. The Vigor routers support VLAN so create a seperate LAN for voice and data. Also see the Vigor Notes below.

How can I use QoS for VoIP?
QoS (Quality of Service Assurance) is a feature on Vigor VoIP routers which gives priority to VoIP traffic. Whereas a file download or web browsing session won't be affected too much by fluctuating bandwidth requirements of your Internet connection, VoIP can suffer in particular, leading to broken up voice. With QoS enabled, VoIP traffic always has highest priority, so the right amount of bandwidth is reserved exclusively for VoIP. If there is no VoIP traffic, the bandwidth it available for all other regular web activities. To enable QoS for VoIP on the Vigor2600V series, enable QoS on the QoS menu - you do not need to select any specific protocols as VoIP has preset highest priority. On the Vigor2500V QoS is always enabled.

Hope this helps.

 
Thanks boredstupid,

We are using the QoS on the drayteks, it just doesn't seem to be very effective.

I thought it might be asking too much of what is essentially a very inexpensive router. Just wondered what other people have tired and succeeded / failed with.

 
Cisco - Cisco - Cisco, if you want real Queuing, Real Fragmentation, real Diffserv intervention and PQ/CBWFQ

I guess you get what you may for !!



ipo.gif
 
Cisco is always a safe bet. Kentrox Q-Series QoS routers are also effective in certain applications. However, ADSL can be troublesome given its asymmetrical characteristics (high speed downstream, slower upstream). ADSL provides little in the way of guaranteed bandwidth, and ISPs typically resell ADSL residential service at a 25-60/1 ratio (subscribers to available bandwidth).

The best approach to your problem may be 2-fold. I would recommend first considering SDSL or other form of symmetrical broadband Internet service, which provides a more reliable and consistent downstream/upstream connection. Many providers also differentiate their DSL offerings by offering "business-class" options. These options typically provide guaranteed bandwidth, limits on cell loss/packet loss, reduced latency and jitter (delay variation). Admittedly business-class options are more expensive but at the same time, you're getting more in the way of (better) service.

In the end, neither SDSL nor ADSL are necessarily better at QOS as it is a function of the higher protocol layers running over DSL to begin with. However, because ADSL Internet is primarily targeted to subscribers who are looking for low cost Internet access, high speed downloads (i.e. web site access, content downloads, etc.) with less need/concern for upstream bandwidth, they offer little or no QoS. Without true end-to-end QoS, your best bet is to pursue as close to a full-duplex connection with minimal latency. Then and only then does good quality QoS hardware come into play.

(Crossing my fingers more providers begin adopting Resource Reservation Protocol (RSVP) so we can all realize the dream of true end-to-end QoS.)
 
try they have some good routers for adsl as well as cable modems that support qos. We have been using and selling these to our customers, we have a scn with 8 sites working well. try use an rdp session/ terminal services and dont download ftp through the home workers use the rdp session instead if you still have problems try installing another adsl at the office for the voice this is quite cheap and will help if your office is the problem also make sure your codecs are set to 729(a)8k. good luck.
 
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