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Part III:
Securing Windows Vista
an internetworking protocol that is used to route packets of data over a network. Two versions
of IP are in use:
■
IP version 4 (IPv4)
IPv4 is the primary version of IP used today on networks, including
the Internet. IPv4 has 32-bit addresses.
■
IP version 6 (IPv6)
IPv6 is the next-generation version of IP. IPv6 has 128-bit addresses.
While many computers use only IPv4, IPv6 is increasingly being used, and eventually IPv4
may be phased out in favor of IPv6. Why? IPv4 allows only 2^32 unique addresses to be used.
While 4,294,967,296 unique addresses might seem like a huge amount, it really isn’t when
you look at the number of computing devices in our connected world. This is why we need
IPv6, with its virtually unlimited address space, and why computers running Windows Vista
have both IPv4 and IPv6 configured by default.
Windows Vista includes many other changes to the core networking components as well.
Windows Vista provides a new implementation of the TCP/IP protocol stack known as the
Next Generation TCP/IP stack. This stack is a complete redesign of TCP/IP functionality for
both IPv4 and IPv6. The Next Generation TCP/IP stack supports:
■
Receive Window Auto Tuning
Optimizes TCP transfers for the host receiving data by
automatically managing the size of the memory buffer (the receive windows) to use for
storing incoming data based on the current network conditions.
■
Compound TCP (CTCP)
Optimizes TCP transfers for the sending host by aggressively
increasing the amount of data sent in a connection while ensuring that other TCP con-
nections are not impacted.
■
Neighbor Unreachability Detection
Determines when neighboring nodes, including
routers, are no longer reachable and reports the condition.
■
Automatic Dead Gateway Retry
Ensures that an unreachable gateway is tried again peri-
odically to determine whether it has become available.
■
Automatic Black Hole Router Detection
Prevents TCP connections from terminating
due to intermediate routers silently discarding large TCP segments, retransmissions, or
error messages.
■
Routing Compartments
Prevents unwanted forwarding of traffic between interfaces by
associating an interface or a set of interfaces with a login session that has its own routing
tables.
■
Network Diagnostics Framework
Provides an extensible architecture that helps users
recover from and troubleshoot problems with network connections.
■
TCP Extended Statistics
Helps determine whether a performance bottleneck for a
connection is the sending application, the receiving application, or the network.
■
Windows Filtering Platform
Provides application programming interfaces (APIs) for
extending the TCP/IP filtering architecture so that it can support additional features.
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