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New Member

ip addressng scheme

Need to assign ip address to our new offices.plan as below

1.head office center-production and DR

3.branch offices-9 center

each office wil have at max 50 users to start with.

datacenters host webservers in DMZ and internal servers.also we will have VPN users.

pls advise on the ip addressing scheme for the setup

let me know if u guys need any more info.

New Member

Re: ip addressng scheme

Hello, not sure what IP range you have but this is how I would work it out,

2^6=64-2=62 hosts per subnet is the mask that allows 62 hosts per subnet

Re: ip addressng scheme

We use IP Addressing like this

• The first octet, 10., is just the class A private IP address block we choose for our network.

• The second octet, 10.X., is to designate which office or building the IP address range is assigned to.

a. Main Site -

b. Site 2 -

c. Site 3 -

d. Site 4 -

• The third octet, 10.X.X., is to designate the VLAN the IP address is a part of.

a. VLAN 1 is Network equipment (routers, switches, etc.)

b. VLAN 3 Lets say is for Servers

c. VLAN 5 Lets say is for Printers

d. Desktop and Laptop VLANS are assigned based on floor of the building. We add 100 to the floor number and we get the VLAN ID based on that, for example, the third octet for 18th floor would be 118, so a user in site 2 would be 10.15.118.X

e. VoIP VLANS are assigned based on floor like the Desktops and Laptops except we add 200 to the floor number. (so that means no floors over 54)

• The fourth octet, 10.X.X.X, is assigned manually or by DHCP depending on the type of equipment.

Here are some examples:

1. - this is a server in Site 3 in VLAN3 and it is either named.

2. -This is a workstation in Site 2 on the 18th floor in VLAN118.

3. - This is a VoIP Phone in Site 2 on the 18th floor in VLAN218.

4. - This is a printer in Site 4 in VLAN5.

5. - This is a piece of network gear in Site 3 and is in VLAN1

Hope that helps,


New Member

Re: ip addressng scheme

thanks for the reply.

we plan to use class B address block.also we plan to have ./24 mask for each office.

can you provide a scheme for our setup as in above post.

sorry,forgot to include the voice.we wil have a seperate voice segment in each office running along with data.can you your thoughts for this also.


New Member

Re: ip addressng scheme

can somebody help in designing the ip address scheme for our network.

plan as below

1.we have 2-datacenters(production and DR) hosting infrastructure,application servers

2.head office

3.branch offices-9 center

we wil use class B addresing scheme (172.16.X.X).we plan to have /24 mask at each branch offices

datacenters host webservers in DMZ,internal servers and also desktop users.we have ASA box to isolate networks.

also we will have Remote access VPN configured in ASA and we are going to have voice network running on same link.

can someone help me out with an ip adddresing example,little confused with data center ip addressing.

another question is how to have ip addresing scheme for voice network.any suggestions.

Thanks in advance.

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