課件教案kuka培訓(xùn)

1、Security on the network FirewallsTasks of a firewall:Prevention of unauthorized access to the local network from the InternetMonitoring of access to Internet resources from the LANLogging of unauthorized access attempts and of services used (ports)Security on the network Firewalls1. ANYTHING WHICH I

2、S NOT FORBIDDEN IS PERMITTED!2. ANYTHING WHICH IS NOT PERMITTED IS FORBIDDEN!Security on the network Firewalls: Functional principlesTYPES OF FIREWALLPacket filterProxy serverNATStaticDynamicStaticDynamicIPs and ports;hosts and servicesOne-wayVarious network ranges;separation of networksSecurity on

3、the network Principles of packet filtersAnalysis of data traffic (by means of IP headers)Condition:Definition of rules, e.g. disable hosts, disable ports (services)Delivery yes / no in accordance with the rulesNo monitoring of the packet contents (data)!No protection against viruses and mail bombing

4、!StaticDynamicSecurity on the network Principles of proxiesCommunication request always sent to the proxyProxy carries out the data exchangeNo monitoring of the data!The connection between the LAN and the Internet exists only virtually.A server handles communication with other networks.The proxy pro

5、vides a cache!Applications must support the proxy service!The proxy keeps a log of the data exchange!Security on the network Principles of NAT (Network Address Translation)LAN addresses are replaced with official addresses (masking)Masks are stored in routing tables.LAN=192.168.10.10 Internet=201.12.13.3Different network ranges are not able to contact