The network stack also makes heavy use of randomization to increase security and reduce the predictability of various values that may be of use to an attacker, including TCP initial sequence numbers and timestamps, and ephemeral source ports. A number of features to increase network resilience and availability, including countermeasures for problems with ICMP and software for redundancy, such as CARP and pfsync, are also included. The project was the first to disable the plain-text telnet daemon in favor of the encrypted SSH daemon, in 1999, and features other integrated cryptographic software such as IPsec. The telnet daemon was completely removed from OpenBSD in 2005 before the release of OpenBSD version 3.8.