Maximum segment size. Clamping this TCP value avoids fragmentation in tunnels like HCX Network Extension and NSX IPsec VPNs and lets NSX Federation carry cross-domain traffic over any MTU; the value is the largest single-segment payload a host will accept, worked out from the egress MTU.
Also called maximum segment size.
Read more: Broadcom TechDocs
In the Ultra Transcenders books
Each book explains MSS in context, with comparison tables and the common traps.
Terms in this definition
- TCP
A transport protocol that is connection-oriented.
- LIKE
Compares strings with a pattern that can contain the % and _ wildcards. Because it only understands character patterns, searching big volumes of text this way is much slower than using full-text search.
- Network Extension
Migrated VMs keep their IP and MAC addresses because this VCF Operations HCX service bridges their networks (VLAN-tagged distributed port groups, NSX segments or NSX VPC subnets) to the remote site through a pair of appliances. Unless Mobility Optimized Networking is used, the default gateway stays at the source.
- NSX
Software that handles networking and security across VCF, covering firewalling, load balancing, NAT, VPCs, overlay segments and Tier-0/1 gateways.
- IPsec
Internet Protocol Security is the set of protocols that negotiates and encrypts the tunnels used by VNet-to-VNet and site-to-site VPNs.
- NSX Federation
An NSX feature that VCF uses to stretch security policy and overlay segments across VCF instances, for example for fleet-level components. A Global Manager federates the Local Managers (NSX Managers) of several locations, so firewall rules, segments and gateways are created once and span them all.
- OVER
Gives a T-SQL window function its window: PARTITION BY, ORDER BY and, if wanted, a ROWS or RANGE frame. Rankings and running totals can then be worked out while every row is kept.
- MTU
Biggest frame an interface can carry. The physical fabric needs at least 1600 bytes for NSX overlay traffic, with 1700 recommended and 9000 preferred where jumbo frames run end to end.
Related terms
- Traffic Engineering
HCX feature set for improving how Network Extension and Interconnect traffic crosses the underlay. It includes encrypting tunnels, Generic Receive Offload, TCP MSS clamping, and Application Path Resiliency (several paths prepared, one used at a time).