TMS zl Management and Configuration Guide ST.1.2.100916

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Glossary
E
EF A Differentiated Services PBH protocol intended to provide for low delay, low
jitter and low loss services.
email forwarding The TMS zl Module sends logs to as many as three email addresses.
encapsulation The process of encapsulating one protocol within another. For example, L2TP
can be encapsulated by IPsec to secure tunnel data.
encapsulation
mode
The method IPsec uses to secure a VPN tunnel. The two encapsulation modes
are tunnel mode and transport mode.
encryption
algorithm
An algorithm that provides data privacy by transforming data into a new string.
DES, 3DES, and AES are encryption algorithms the TMS zl Module uses to
establish security associations (SAs).
endpoint A device that connects to a network, such as a desktop computer, a laptop
computer, or a server.
ESP Encapsulating Security Protocol. A part of the IPsec protocol suite that
provides origin authenticity, integrity, and confidentiality protection for pack-
ets.
exchange method See key exchange method.
exchange mode See key exchange mode.
expedited
forwarding
See EF.
extended ACL extended Access Control List. On the TMS zl Module, the extended ACL is
called the traffic selector. The term extended ACL is used on the HP Secure
Router 7000dl series.
eXtended
AUTHentication
See XAUTH.
extended cipher
block chaining
See AES-XCBC.
extended
sequence number
An IPsec option that allows the you to extend the sequence of numbers used
in an SA. By default, the number is 2
32
, and the extended sequence number is
2
64
. This is helpful if your SA has a relatively long lifetime and transmits a great
deal of traffic.
External The firewall zone that describes everything outside the autonomous system.