Week 4 Tutorial Flashcards
What is the structure of an IPv4 address?
a 32-bit number that uniquely identifies a network interface on a machine
What is the prefix of an IPv4 address?
dotted decimal netmask, this defines where it goes
What is the subnet mask?
the bitmask that when applied by a bitwise AND operation to any IP address in the network, yields the routing prefix.
What is the TTL for a DNS?
setting for each DNS record that specifies how long a resolver is supposed to cache the query before it expires and a new one needs to be done
Why is caching DNS results close to client useful?
resolver uses record from cache instead of querying the server again
What is the iterative mode of a DNS server?
a DNS server is queried and it returns answer without querying other DNS servers even if it cannot produce an answer
What is the recursive mode of a DNS server?
takes website name or URL request from user and checks the records attained from DNS servers for assosiated IP. Might also query other servers for answer.
How are the 2 modes of DNS servers used?
recursive has a lot of security issues, but iterative only queries the one server so the two have drawbacks. As both have different advantages and disadvantages adds scalability and distribution
why can the UdpClient1 program can run and transmit even when UdpServer1
program is not running
as it is connectionless, so does not rely on a connection to set up to do processes
why cant the TdpClient1 program can run and transmit even when TdpServer1
program is not running
it is connection orientated
connection must be in place before anything can happen
How does multicast IP address differ to a unicast IP address?
multicast sends IP packets to a group of hosts on a network, whereas unicast sends to a singular host
