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| Working with the Intelligent Packet Processor (IPP) Module | SmartNA-X 1G/10G Modular
SmartNA-X
™
1G/10G User Guide 1.4
©
2015 Network Critical Solutions Limited
CONTROLLER>
select slot 1
SLOT1>
set port A packetprocessor transform 7 "remove v2 header"
Step 5: Optionally set a packet slicing size to a port
The next step is to optionally slice packets egressed from a IPP port to a given length. When slicing is applied, all packets
egressed will be no longer than the specified Slice length, which is defined in bytes and includes the CRC bytes.
In the following example, packets egressed from port 1A are sliced to 756 bytes:
SLOT1>
set port A packetprocessor slicing 756
Step 6: Map traffic to and from the port
The penultimate step is to map the IPP ports to and from other ports in the chassis. Since the IPP module has no physical
ports, packets can only enter and leave the module by mapping to/from other modules in the chassis.
SLOT1>
set map 4a to 1a
SLOT1>
set map 1a to 4b
Step 7: Commit changes to the system
The final step to setting up the IPP module is to review the pending port configuration changes. If the changes are correct,
commit them to update the system configuration, otherwise use the
cancel packetprocessor
command to discard them.
SLOT1>
show port A
port type : Packet processor
slicing : 756
transforms :
7: "remove v2 header"
SLOT1>
commit
Example Transforms
The GRE packet arrives with a delivery (IP) header and GRE header that we want to strip, leaving the encapsulated IP
header and payload.
IPv4 headers and GRE headers have variable size. A single Transform detects and strips headers of a specific size. Up to 8
transforms could be used to detect and strip headers of 8 different sizes.
Standard transforms are provided for cases where the transport header is IPv6 or a 20 byte IPv4.
Removing delivery header and 3 word GRE header from an untagged IPv4 or IPv6 packet
A Transform to match and remove the GRE or PPTP GRE header using Key and Sequence fields (but not Checksum or
Acknowledgement. This applies to untagged IPv4 packets.
Matches:
EtherType-IPv4
IPv4-IHL=5
GRE-KS-L=3-IPv4
The required action is to delete the 5 word IPv4 header and the 3 word GRE header, a total of 32 contiguous bytes.
Action:
action 112 delete 32
To do the same to IPv6 packets we need a second transform.