Network Design | IP telephony Design

We were asked to create an ip telephony topology earlier for 25 users that is scalable to 100 users.
We were also asked to proposed what routers and switches to use. I'm not good w/ this. This is my first networking job so i'm not sure if i'm doing it right.

Btw, this is for small business client. As you can see, do i still need a router gateway on this topology? There's no redundancy here since there's currently 25 users. Is it correct to say that my endpoints here are the ip phones, pc, firewall and the gateway?

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Comments

Mow

I haven't used the BE6000S yet, but I believe it is its own gateway, no need for the 2901. Also, since this is a Cisco design, the phones have a built-in switch that will allow you to use one network drop for phone and pc. Don't forget to use a separate VLAN for phones!

Deathmage

the 3560 is a 10/100 mbit switch, that network would be switching at 100 mbit's. I'd personally get a 3750G if your going on the low-end so at-least the core would be gigabit. My only thought for this is the wireless connection from the controller would have compounded connections going into the 3560 @ 100 Mbits.

Overall though the network design looks fine, just the switching would only be 100 Mbit's with the above switches. The customer may complain about speed for web browsing and for VOIP. Make sure you use QoS on the VOIP/Phone systems and are on their own vlan for sure.

echo_time_cat

Neurotic. What kind of connection to the PSTN do you have? Is it a T1?

I ask because I initially was wondering about your firewall placement, but then realized you may have had separate WAN connections for both.

If it's scalable to 100 users though, I find myself doubting it's a single T1.

Also, what model of ipPhones do you plan on deploying?

Mow

T1 is plenty for many SMB that size. I assume there was a call volume survey done, so they should know how many calls are active at any give time.

Any POTS lines in case the T1 is down and 911 needs to be dialed?

echo_time_cat

Mow wrote: »

T1 is plenty for many SMB that size. I assume there was a call volume survey done, so they should know how many calls are active at any give time.

Any POTS lines in case the T1 is down and 911 needs to be dialed?

For 25 users yes, depending on the codec, but up to 100 users? (I'm imagining simultaneous calls when considering this).

https://supportforums.cisco.com/discussion/10612331/how-many-simultaneous-voice-communication-t1

How many calls can I make over my T1 with hosted voice?

Iristheangel

He has a 3650 in his diagram, not a 3560. He will get full gig on the 3650. If you need a switch above that for whatever reason, go the 3850. They are priced the same as the 3750s and much newer so you'd have a longer life than the 3750s but I don't think you'd need to move to a larger switch in this small of an environment though I would recommend putting some redundancy in you core. If that 365p is a 48 port L3 switch, maybe consider 2x 24-port 3650's. You can stack the 2960-Xs to them

ninjaturtle

Mow wrote: »

I haven't used the BE6000S yet, but I believe it is its own gateway, no need for the 2901. Also, since this is a Cisco design, the phones have a built-in switch that will allow you to use one network drop for phone and pc. Don't forget to use a separate VLAN for phones!

We are currently looking at the BE6000 system to replace our super old Call Manager 4.1 solution. With the BE6000 solution you could trunk directly to the Call Manager if an internal trunk from another trusted system communicating over SIP. However when you have a SIP trunk from a carrier you would never have them directly trunk as it's a huge security hole and your system could get hacked. So with the router you can terminate a SIP trunk to it or connect physical PRI's depending on what you wanted for PSTN.