Unified Services Router    User Manual 
18 
As  with  an  IPv4  LAN  network,  the  router  has  a  DHCPv6  server.  If  enabled,  the 
router  assigns  an  IP  address  within  the  specified  range  plus  additional  specified 
information to any LAN PC that requests DHCP served addresses.  
The following settings are used to configure the DHCPv6 server: 
  DHCP Mode: The IPv6 DHCP server is either stateless or stateful. If stateless is 
selected  an external IPv6 DHCP  server  is  not required as the IPv6  LAN hosts 
are auto-configured by this router. In this case the router advertisement daemon 
(RADVD)  must  be  configured  on  this  device  and  ICMPv6  router  discovery 
messages  are  used  by  the  host  for  auto-configuration.  There  are  no  managed 
addresses to serve the LAN nodes. If stateful is selected the IPv6 LAN host will 
rely on an external DHCPv6 server to provide required configuration settings 
  The domain name of the DHCPv6 server is an optional setting 
  Server Preference is used to indicate the preference level of this DHCP server. 
DHCP  advertise  messages  with  the  highest  server  preference  value  to  a  LAN 
host  are  preferred  over  other  DHCP  server  advertise  messages.  The  default  is 
255. 
  The  DNS  server  details  can  be  manually  entered  here  (primary/secondary 
options.  An  alternative  is  to  allow  the  LAN  DHCP  client  to  receive  the  DNS 
server  details  from  the  ISP  directly.  By  selecting  Use  DNS  proxy,  this  router 
acts  as  a  proxy  for  all  DNS  requests  and  communicates  with  the  ISP‘s  DNS 
servers (a WAN configuration parameter). 
  Primary  and  Secondary  DNS  servers:  If  there  are  configured  domain  name 
system (DNS) servers available on the LAN enter the IP addresses here.  
  Lease/Rebind time sets the duration of the DHCPv6 lease from this router to the 
LAN client. 
IPv6 Address Pools 
This  feature  allows  you  to  define  the  IPv6  delegation  prefix  for  a  range  of  IP 
addresses to  be  served  by  the  gateway‘s  DHCPv6  server. Using a delegation prefix 
you can automate the process of informing other networking equipment on the LAN 
of DHCP information specific for the assigned prefix. 
Prefix Delegation 
The following settings are used to configure the Prefix Delegation: 
  Prefix  Delegation:  Select  this  option  to  enable  prefix  delegation  in  DHCPv6 
server.  This  option  can  be  selected  only  in  Stateless  Address  Auto 
Configuration mode of DHCPv6 server.