Specifying IPv4 Addressing Assignment in Layer 3 VPN Service Definitions
You, the Service Designer, can specify the IPv4 IP address settings to use for PE/CE link when provisioning Layer 3 VPN service definitions.
When configuring Layer 3 VPNs, it is necessary to assign consistent IP addresses to the logical interfaces on both sides of each PE/CE link. The IP addresses assigned to each PE/CE link need to allow routing across the customer’s entire Layer 3 VPN, and only need to be unique within the confines of the customer’s VPN, as long as the PE/CE addresses are not exposed outside of that VPN. If the PE/CE link addresses are accessible from outside of the customer’s VPN, then those IP addresses may also need to be globally unique across the Internet, instead of just within the customer’s VPN.
The Network Activate application automatically assigns IPv4 addresses to both sides of each PE/CE link, as well as keeps track of which IPv4 addresses are already in use. It ensures the correct assignment of IP addresses and prevents the reuse of IP addresses.
To specify auto-assigning of the PE/CE link addresses from IPv4 pools, you select the Auto Pick option, the IP pool type—global or customer, and the number of contiguous IPv4 addresses—size of the IPV4 address block that is allocated for each PE/CE link. Which particular global or customer IPv4 address pool to use is chosen during service provisioning when filling out the L3VPN Service Order.
For auto-assignment scenarios, the service designer can always select the Allow editing in Service Order option at the right of each service definition setting to allow the corresponding IPv4 pool setting to be overridden later when filling out the L3VPN Service Order.
To specify manual assignment of PE/CE link addresses, the designer simply selects the manual-assignment option.
To specify IP address settings in a Layer 3 VPN service definition:
- In the IP Address Settings area PE Interface
IP Address drop-down list box, select one of the following:
Auto Pick—Specifies whether PE/CE link addresses are automatically assigned from an IPv4 IP address pool.
Select Manually—Specifies whether the service designer manually assigns PE/CE link addresses from the same IPv4 IP address pool.
- In the IP pool types drop-down list box, select
one of the following:
Global—Pools of IPv4 addresses pertaining to the Service Provider. There can be more than one global IPv4 address pool. However, each global pool must have its own unique name and its set of IPv4 addresses must not overlap with those of any other global pool. You can allocate addresses from global pools across multiple Layer 3 VPN across multiple customers.
Customer—Pools of IPv4 addresses pertaining to a particular customer. These pools are associated with the corresponding customer. There can be more than one customer IPv4 pool associated with each customer. However, each customer pool must have its own set of IPv4 addresses which must not overlap with those of any other pool belonging to the same customer. Addresses from customer pools can be allocated across multiple Layer 3 VPNs for a particular customer.
- In the Size of address block field, enter the size of the IPv4 IP addresse block allocated for each PE/CE link.
- Select the Editable in service order check box on the right of each IP address setting to overwrite the corresponding IPv4 IP address pool setting when creating the service order.
- Click another Layer 3 VPN Settings link to continue specifying
settings or click Finish.
If you click Finish, the custom Layer 3 VPN service definition appears on the Manage Service Definitions inventory page.