can you solved vslm addressing plz ?

ll

terryboob,

The exercise is quite a big one and requires a bit of math.

Here's what I would have done (if anyone has an alternative method, feel free to post it).

Site No1 has 4 departments with 150,100, 92 and 58 users respectively.

We'll assign one subnet for each department. The subnet's size will depend on the number of users each department has.

150 users requires at least a /24 (255 IPs) subnet mask, or 255.255.255.0
100 users require a /25 (128 IPs) subnet mask, or 255.255.255.128
92 users require a /25 (128 IPs) subnet mask, or 255.255.255.128
58 users require a /26 (64 IPs) subnet mask, or 255.255.255.192

So, putting things into place, we can start building our map using the 172.16.0.0 network according to the above:

172.16.0.0 /24 (150 user department) [ ip range 172.16.0.1 - 172.16.0.254]
172.16.1.0/25 (100 user department) [ ip range 172.16.1.1 - 172.16.1.126]
172.16.1.128/25 (92 user department) [ ip range 172.16.1.129 - 172.16.1.254]
172.16.2.0/26 (58 user department) [ ip range 172.16.2.1 - 172.16.2.62]

Lastly, I've figured that if your using the three layer hierarchical model, that means you need access, distribution and core layer switches:

400 users / 48 (assuming 48 port switches) = around 9 access layer switches

I'd place two 24 port distribution switches and one core layer switch, plus the 2600 router.

In total, that's 9 + 2 +1 +1 = 13 IP's.

A /28 prefix or 255.255.255.240 subnet mask gives us 14 useable ip addresses. Here's the final network:
172.16.2.64/28 (13 ip's for our switches & router) [ ip range 172.16.2.65 - 172.16.2.78]

So, if my math calculations are correct, here's the total breakdown for your first site:

172.16.0.0 /24
172.16.1.0/25
172.16.1.128/25
172.16.2.0/26
172.16.2.64/28

You'll need to perform the same breakdown for your 2nd site, and then add your WAN link to that as well, which is quite easy as WAN links commonly use /30 (2 usable ip addresses) for point to point connections.

I hope that helps you towards your answer.

Cheers,

cris.....thanks for ur time
i will compare it to what i have got ......but the problem is ........do i need to configure routing protocols on the routers.....because we have routers on each departments maybe that will give more performances .......

I put a 4510 at one location and a 4506/4507 at the other location. If you got that many hosts, you don't want to rely on fix switches.

do i need to configure routing protocols on the routers.....because we have routers on each departments maybe that will give more performances .......

Sure you need to configure routing protocols. Thats if you want your vlans to be able to communicate together. You could also use static routing (but thats not easily administered and I don't recommend for your case).

thanks solo,,,,,,,

Sure you need to configure routing protocols. Thats if you want your vlans to be able to communicate together. You could also use static routing (but thats not easily administered and I don't recommend for your case).

ok then .im just confused that why routing protocol need to be configured i thought that im building vlans network using hierarchical model network .............what do u reckons....solo ? what about dynamic routing and which routing protocols do u recommended ? is it ospf..? or rip v2.....remember each router on each floors has the same router 2600 series router ?....