4 IP Addressing and Routing Free Online FlashCards

How long is an IPv4 address?

IPv4 addresses are 32 bits long and are written as four decimal octets.

What does an IPv4 /24 prefix indicate?

A /24 prefix means the first 24 bits identify the network, leaving 8 bits for hosts.

What addressing assumption did CIDR replace?

CIDR allows networks of any prefix length rather than requiring fixed address classes.

Which IPv4 ranges are reserved for private networks?

The private IPv4 ranges are 10.0.0.0/8, 172.16.0.0/12, and 192.168.0.0/16; they are not intended for routing across the public Internet.

How are IPv6 addresses sized and written?

IPv6 addresses are 128 bits long and are written as eight groups of hexadecimal digits separated by colons.

What are the IPv6 address-shortening rules?

Leading zeros within a group may be omitted, and one consecutive run of all-zero groups may be replaced by :: once in an address.

Which address types does IPv6 support, and which does it lack?

IPv6 supports unicast, multicast, and anycast addresses, but it does not use IPv4-style broadcast addresses.

What is the IPv6 link-local prefix used for?

The fe80::/10 prefix is used for IPv6 link-local addresses, which operate on a local link.

How does longest-prefix match select a route?

It selects the matching route with the most leading bits in common with the destination address.

What information does a routing-table entry commonly contain?

A route commonly records a destination prefix, next hop, outgoing interface, and metric or preference.

What does the IPv4 default route do?

The IPv4 default route, 0.0.0.0/0, provides a next hop for destinations not matched by a more specific route.

What must be true for a static route to work?

An administrator configures it. Its next hop must be reachable and a return path must exist; it will not adapt to failures unless tracking or failover is configured.