Networking is one of the foundational elements on which advanced capabilities of new age ADCs are built. To be able to deploy ADCs in a variety of scenarios with varied L2/L3 devices, it is important to have standards based implementation with configuration options to fine tune for specific scenarios. Many new trends – like evolution of IPv6, new developments in Data Center technologies etc. – are shaping the way ADCs are deployed in the world of business with ever increasing reliance on always available applications.
As with every release, NetScaler 10, introduces many new enhancements, optimizations and features that continue to enable new use cases for our customers.  Some of the key networking features introduced in NetScaler are:
  1. Policy Based Routing (PBR) for IPv6: PBR for IPv4 has been around in NetScaler for long and is heavily used by customers to make custom routing decisions based on matching conditions in traffic rather than simply relying on the routing tables. Policies can be defined on a combination of L2, L3 and L4 parameters like IPs, Ports, MAC, VLAN etc. NetScaler 10 support PBR for IPv6.
  2. Direct Server Return (DSR) in L3 mode for IPv6: DSR enables servers to directly reply to clients without return traffic going through NetScaler. DSR is useful in some high volume environments when session management is not necessary on NetScaler. DSR increases the overall capacity of NetScaler as only one way traffic passes through it. DSR for IPv6 in L2 mode was introduced in previous releases but with NetScaler 10, support for L3 mode DSR for IPv6 has also been introduced.
  3. ISIS Routing Protocol: ISIS routing protocol is a link state routing protocol (like OSPF) that operates over L2. ISIS is still widely used and many times for legacy reasons. NetScaler already supports RIP, BGP and OSPF for both IPv4 and IPv6 and with this latest release, NetScaler has added ISIS support for both IPv4 and IPv6 as well.
  4. Network Profile Support: Network Profiles is a powerful feature that provides flexibility to administrators to control the Source IPs used in communication initiated by NetScaler to backend server. Control over source IP helps in many situations where servers need to differentiate between client traffic versus monitoring traffic or different servers are catering to different departments and access control is enforced based on the IPs. Network Profiles can be bound to monitors for health monitoring traffic, services and vservers for actual data traffic.
  5. Link Load Balancing (LLB) for IPv6: Link Load balancing is used to manage the outgoing traffic (to internet) from enterprises that use multiple ISP links for redundancy. LLB ensures optimal distribution of traffic based on variety of Load Balancing algorithms ensuring optimization and redundancy in case of failed links. LLB is now supported for IPv6 links as well.
  6. IPv6 Reverse NAT (RNAT): RNAT for IPv6 to IPv6 source IP translation is also supported in NetScaler 10.
  7. Access Control Lists (ACLs): There are two enhancements in ACLs in NetScaler 10 for ACLs
  8. – 1) Flush: When simple ACLs are created, they take effect on the new sessions – but to make simple ACLs effective on existing sessions as well, “flush” command can be used 2) Number of ACLs: Limit for the number of extended ACLs that can be created on NetScaler has been increased to 10K from 1K

    Many other enhancements has been introduced, like:
  1. Support /31 networks
  2. SNMP agents over IPv6
  3. Extension Header Parsing for IPv6 for  accurate identification for L4 protocols for enforcing policies
  4. Gateway health monitoring on both nodes in a HA deployment to ensure proper failover