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softwire-types (Next Gen Services)



Hierarchy Level

Release Information

Statement introduced in Junos OS Release 20.2 for Next Gen Services on MX240, MX480 and MX960.


Configure ds-lite, 6rd and MAP-E softwire objects.


The following options are available for each type of softwire:

ds-lite Specify options for DS-Lite softwites.
v6rd Specify options for v6rd softwites.
map-e Specify options for map-e softwires.
auto-update-mtuThis option is not currently supported.
copy-dscp Copy DSCP information to IPv4 headers during decapsulation.
flow-limit —Maximum number of IPv4 flows per softwire.
ipv4-prefix IPv4 prefix of the customer edge (CE) network
mtu-v4Maximum transmission unit (MTU), in bytes (576 through 9192), for IPv6 packets encapsulated into IPv4. If the final length is greater than the configured value, the IPv4 packet is dropped. This option is mandatory except for DS-Lite softwires since it depends on other network parameters under administrator control.
mtu-v6Maximum transmission unit when encapsulating IPv4 packets into IPv6. If the final length is greater than the MTU, the IPv6 packet is fragmented. This option is mandatory since it depends on other network parameters under administrator control.
session-limit-per-prefixMaximum number of sessions per B4 subnet prefix.
softwire-concentrator Specify the IP address of the softwire concentrator.
softwire-typeSets softwire concentrator type to 6rd.

Values: v6rd

v6rd-prefixIPv6 prefix for the 6rd domain.

For map-e softwires:

Options for MAP-E rules:

nameName of the MAP-E softwire domain name.
br-addressSpecify the Border Relay (BR) device unicast IPv6 address as the softwire concentrator IPV6 address.
version3(Optional) Configure version number to distinguish between currently supported version of the Internet draft draft-ietf-softwire-map-03 (expires on July 28, 2013), Mapping of Address and Port with Encapsulation (MAP) and the latest available version.
rule Specify the name of Map-E the rule.
v4-reassembly | v6-reassembly(Optional) Enable IPv4 and IPv6 reassembly for MAP-E.
disable-auto-routeDisable auto-routes and enable static routes to facilitate ECMP load balancing.

When you enable the disable-auto-route option, you must configure static routes.

ipv4-prefixConfigure rule for IPv4 prefix of the MAP-E domain.
ipv6-prefixConfigure rule for IPv6 prefix of the MAP-E domain.
ea-bits-lengthConfigure rule for Embedded Address (EA) length for the MAP-E domain.

Range: 0 through 48

psid-lengthConfigure Port Set ID (PSID) length value for the MAP-E domain.
  • If the sum of v4-prefix-len and ea-bits-len is less than 32, then the psid-len must be equal to the difference between 32 and the sum total of v4-prefix-len and ea-bits-len.

Range: 0 through 16

psid-offset(Optional) Configure PSID offset value for the MAP-E domain.

Default: 4

Range: 0 through 16

mtu-v6(Optional) Specify the Maximum transmission unit (MTU) for the MAP-E softwire tunnel.

Default: 9192

Range: 1280 through 9192

Required Privilege Level

interface—To view this statement in the configuration.

interface-control—To add this statement to the configuration.

Related Documentation