
Securely Managing the Core Network 239
Two ways to avoid this problem are to
• Turn auto-summary off at the CE
• Use route distribution filtering at the PE
NOTE We have presented a generic overview of CE management in terms of the link technology
implemented. However, there are potentially a variety of emerging applicable configurations,
such as Frame Relay, ATM, or VLAN encapsulation on the link, and a VRF on the CE that
retains the management (logical) link, thus resulting in a completely separated VPN data
link. This solution can avoid address conflict, and the management security is consequently
higher due to the VPN separation. We recommend ...