Welcome to the Cisco Networking Professionals Ask the Expert conversation. This is an opportunity to discuss IP Telephony using Catalyst switches with Cisco expert Chris Cullen. Chris has been in the data networking industry for the past 14 years and is currently a product manager at Cisco. Feel free to post any questions relating to IP Telephony using Catalyst switches.
Chris may not be able to answer each question due to the volume expected during this event. Our moderators will post many of the unanswered questions in other discussion forums shortly after the event. This event lasts through November 17. Visit this forum often to view responses to your questions and the questions of other community members.
We are looking at implementing a Catalyst 6000 voice T1 service module. Exactly what functions can this piece of equipment provide me? Any help would be appreciated.
The Voice T1 and Services module has the power to provide Voice Services for 8 x T1 trunks (192 channel or DS0 trunks) through either the 8 physical interfaces on the module or through Virtual interfaces via the LAN, or a combination of each. For example a Catalyst 6000 with a Voice T1 and Services module installed can provide a T1 gateway to the PSTN and another to a PBX and have 6 remaining for Voice Services. These Voice Services could be G723 to G711 compression services or conferencing facilities.
I'm doing some research on the Catalyst 4000 series and the Catalyst 3524-PWR for a customer. I was wondering if you could help me determine the differences between the two?
The Catalyst 3500 series XL is a stackable 10/100 and Gigabit Ethernet switch. It is ideal for customers who require a low entry price, but need the flexibility to simply and affordably scale workgroups beyond 12, 24, or 48 ports.
The Catalyst 4003 and 4006 are flexible, modular 10/100/1000 wiring closet switches. They are ideal for customers who require a cost-effective modular chassis supporting up to 96 or 240 10/100 ports in a single system, and who value the ability to enhance the functionality of the system over time without sacrificing their original investments. They also provide an integrated LAN, WAN and voice solution for the enterprise branch office. An integrated solution is great for customers seeking to reduce network complexity.
One of the other main differences between the 3524-PWR and the 4K is the avilabilty of DSP resources within the 4K which provide transcoding (G.729 or G.723 to G.711 for conferencing or voicemail), conference bridges, and MTP (for supplementary services (hold, transfer, etc) when calling from an IP phone to a H.323 endpoint)
The DSP option is required when voice functionality is enabled. This includes any voice gateway functions or voice network services. Along with the DSP option, the Cisco IOS IP/Firewall/DSP Plus feature set is required.
I would like to understand what I need to enable QoS at layer 2 only with the C6K. As you know there is I/O module with "enhanced QoS" capabilities but this one is enabled at Layer 2 or Layer 3 ? Do I need only the Supervisor module to enable QoS at L2 ? When do I need the PFC ?
I presume taht MSFC + PFC is for L3 QoS ?
Thank you for your help
To enable basic QoS at layer 2 you only need the Supervisor module. The Policy Feature card will enable enhnaced Qos services such as ACL, policy and classication. The MSFC enables Layer 3
We have ordered the Lan based ip telephony solution, my question is how will this technology integrate with our existing infrastructure, mainly our 6509 and multiple 2948Gs, more specifically can the 2948Gs support auxiliary vlans and if not what would the impact be if we run the phones and pcs in one vlan ?
The Catalyst 6509 provides full IP Telephony support, which includes: Inline Power 10/100 switching modules, FXS modules, T1/E1 gateways, DSP farms for conferencing and transcoding, Aux. VLANs and QoS. The Aux. VLAN feature was introduced in Cat OS 5.5.1 so provided you are running this Cat OS and the switch supports 802.1p/q the Aux. VLAN feature is functional.
In a nutshell, IP telephony is a form of Voice over IP. The first voice over IP networks were built with regular analog phones or PBX trunks plugged into routers and carried across the IP network and "pop" out the other side.
With IP telephony the endpoint is now the telephone itself which means that every users phone call is a voice over IP call to another IP phone on the network or to a gateway on your network that will connect you to the outside world.