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The first level of security is physical. Passwords can be used to limit access to users that have been given the password. The login banner can be used to display a message before the user is prompted for a username. Telnet sends session traffic in cleartext; SSH encrypts the session traffic. Port security can be used to limit MAC addresses t...
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Displays the configuration of the system hardware, software version, names and sources of configuration files, and boot images Displays the current active configuration file of the switch Displays statistics for all interfaces configured on the switch
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Station D sends a frame to station C. Switch caches the MAC address of station D to port E3 by learning the source address of data frames. The frame from station D to station C is flooded out to all ports except port E3 (unknown unicasts are flooded).
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Cisco SDM is a useful tool for configuring Cisco access routers. Cisco SDM contains several easy-to-use wizards for efficient configuration of Cisco access routers. Cisco SDM allows you to customize Cisco access router configurations using advanced features.
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Cisco IOS Software includes a full DHCP server implementation: Assigns IP addresses from specified address pools within the router Can be configured to assign the IP address of these components: Domain Name System (DNS) server Default router
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Transition richness means: No fixed day to convert; no need to convert all at once Different transition mechanisms are available: Dual stack Manual tunnel 6to4 tunnel ISATAP tunnel Teredo tunnel Different compatibility mechanisms: Proxying and translation (NAT-PT)
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Point-to-point Subinterfaces act like leased lines. Each point-to-point subinterface requires its own subnet. Point-to-point is applicable to hub-and-spoke topologies. Multipoint Subinterfaces act like NBMA networks, so they do not resolve the split-horizon issues. Multipoint can save address space because it uses a single subnet. Multipoi...
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This is an example of the Santa Cruz router authenticating to the HQ router. Hash values, not actual passwords, are sent across the link. The local router or external server is in control of authentication attempts.
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There are three types of NAT: static, dynamic, andoverloading (PAT). Static NAT is one-to-one address mapping. Dynamic NAT addresses are picked from a pool. NAT overloading (PAT) allows you to map many inside addresses to one outside address. Use the show ip nat translation command to display the translation table and verify that translation...
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Follow these steps to determine the subnetwork and host addresses using a subnet mask: Write the octet being split in binary. Write the mask in binary and draw a line to delineate the significant bits. Cross out the mask so you can view the significant bits. Copy the subnet bits four times. Define the network address by placing all zeroes in t...
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