Chapter 8: Firewall's
what is the ranger for Well Known ports?
0 to 1023
what is the range for registered ports?
1024 to 49151
What is the range for dynamic (private) ports?
49152 to 65535
what are filtering rules also known as?
ACLs (access control lists)
What is port 67 and 68?
DHCP
what is port 53?
DNS
what ports 20 TCP and UDP and 21 TCP and UCP?
FTP (file transfer protocol)
what is port 80?
HTTP
what is port 119?
NNTP ( network news transport protocol)
what is port 123?
NTP ( network time protocol).
what is port 110?
POP3
what is port 25?
SMTP (simple mail trasfer protocol)
what is the 22 port?
SSH ( Secure Shell)
what is port 69?
TFTP (trivial file transfer protocol)
what is the 23 port?
Telnet.
What does a DMZ do?
a buffer network that sits between the private network and an un trusted network such as the internet.
What is a host based firewall?
a firewall installed on a single computer.
what is a network based firewall?
a firewall installed on the edge of a private network or network segment.
What is a packet filtering firewall?
a firewall makes decision about which network traffic to allow by examining info in the IP packet header.
what is a network port?
a logical connection to be used by protocols in the upper layers of the OSI model.
what is a forward proxy?
a server that handles request's from inside a private network out to the internet.
what is a reverse proxy?
a server that handles request's from the internet to a server located inside a private network.
What is a firewall?
a software or hardware based network security system that allows or denies network traffic to a set of rules.
what is a standard ACL?
can filter only on source hostname or host ip address. should be placed as close to the destination as possible. use ranges 1-99 and 1300-1999.
What is an Application-level gateway?
capable of filtering based on info contained within the data portion of a packet.
What is a unified threat management device (UTM)?
combines multiple security features into a single network appliance.
What is a DMZ?
demilitarized zone.
what is a transparent firewall?
layer 2 firewall not seen as a router hop by connnected devices.
At what layer of the OSI model does a Packet filtering firewall operate?
layer 3
At what layer of the OSI model does the circuit-level proxy operate?
layer 5
At what layer of the OSI model does a Application- level gateway operate?
layer 7
What is a circuit-level proxy?
makes decisions about which traffic to allow based on virtual circuits or sessions.
What is a routed firewall?
transmitting data through this type of firewall counts as a router hop. supports multiple interfaces. layer 3 firewall
