Networking
Configuring a VLAN
Cisco ISA500 Series Integrated Security Appliances Administration Guide 140
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•Option 150: Supports a list of TFTP servers (2 TFTP servers). Enter the IP
addresses of TFTP servers. Separate multiple entries with commas (,).
NOTE: Enterprises with small branch offices that implement a Cisco IP
Telephony Voice over IP solution typically implement Cisco CallManager at
a central office to control Cisco IP Phones at small branch offices. This
implementation allows centralized call processing, reduces the equipment
required, and eliminates the administration of additional Cisco CallManager
and other servers at branch offices. Cisco IP Phones download their
configuration from a TFTP server. When a Cisco IP Phone starts, if it does not
have both the IP address and TFTP server IP address pre-configured, it
sends a request with option 150 or 66 to the DHCP server to obtain this
information.
STEP 5 In the IPv6 Setting tab, specify IPv6 addressing for the VLAN if you enable the
IIPv4 or Pv6 mode.
•IPv6 Address: Enter the IPv6 address based on your network requirements.
•IPv6 Prefix Length: Enter the number of characters in the IPv6 prefix.
The IPv6 network (subnet) is identified by the prefix, which consists of the
initial bits of the address. The default prefix length is 64 bits. All hosts in the
network have the identical initial bits for the IPv6 address. The number of
common initial bits in the addresses is set by the prefix length field.
STEP 6 Click OK to save your settings and close the pop-up window.
STEP 7 Click Save to apply your settings.
STEP 8 If you want to reserve certain IP addresses for specified devices, go to the
Networking > DHCP Reservations page. See Configuring DHCP Reser ved IPs,
page149. You must enable the DHCP Server or DHCP Relay mode for this
purpose.