WebSphere Application Server V7.0: Concepts ... - IBM Redbooks

WebSphere Application Server Proxy
The WebSphere Application Server Proxy is a proxy server you configure in a
WebSphere Application Server Network Deployment cell. This proxy runs inside
the secure zone of the network as an application server and has access to cell
information and the current state of all servers and applications inside the cell.
5.2.3 Domain and protocol firewall
A firewall is a hardware and software system that manages the flow of
information between networking zones like the Internet and an organization's
private network. Firewalls can prevent unauthorized Internet users from
accessing services on private networks that are connected to the Internet,
especially intranets. In addition, firewalls can block some virus attacks, if those
viruses attacks have to cross the network boundaries protected by the firewall.
Another typical usage of firewalls is to prevent denial of service attacks against
services.
A firewall can separate two or more parts of a local network to control data
exchange between departments, network zones, and security domains.
Components of firewalls include filters or screens, each of which controls
transmission of certain classes of traffic. Firewalls provide the first line of defense
for protecting private information. Comprehensive security systems combine
firewalls with encryption and other complementary services, such as content
filtering and intrusion detection.
Firewalls control access from a less trusted network to a more trusted network.
Traditional firewall services include the following implementations:
► Screening routers (the protocol firewall)
Prevents unauthorized access from the Internet to the DMZ. The role of this
node is to provide the Internet traffic access only on certain ports and to block
other IP ports.
► Application gateways (the domain firewall)
Prevents unauthorized access from the DMZ to an internal network. The role
of a firewall allows the network traffic originating from the DMZ and not from
the Internet. It also provides some filtering from the intranet to the DMZ. A pair
of firewall nodes provides increasing levels of protection at the expense of
increasing computing resource requirements. The protocol firewall is typically
implemented as an IP router.
136 WebSphere Application Server V7.0: Concepts, Planning, and Design