Internet Protocol Options - Wikipedia

Securing Routers by Disabling Unused Router Services and ip classless. The ip classless command is enabled on the Cisco routers by default in version 12.0 and higher. Disable ip classless if your network does not have a subnetted range of IP addresses. If you are subnetting a block of IP address allocated to you by the American Registry for Internet Numbers (ARIN), you should ensure that ip classless is enabled. Question - The ip source-route command allows packets to specify their own routes, this opens up a possible attack. I see this concept in my CCNA studies in NetAcad where the recommendation is disabling this feature. Here is a blog where explain about it: Network Engineer Blog: What is IP Source Routing? Cisco Router/Switch Common Security Vulnerabilities and IP Source Route: IP Source Route allows a sender of an IPv4 datagram packet to specify the route the IPv4 datagram packet takes through the network. IP Source Route allows an attacker to control the path which the IPv4 datagram packet travels. To disable IP Source Route, use "no ip identd" command from the Global Configuration mode.

Description. This command allows the router to route packets that contain source-routing options. (Source routing is an IP option that allows the packet to specify the route it should take to its destination.) Source routing is a potential security problem, so it is best to disable this feature unless required.

Source routing (specified in RFC 791 I believe) is where you specify the route that packets take though the network. There are options in the IP header (Option 3?) that can be set to specify the routers that a packet should pass through on the way to its destination. There are 2 modes of source-routing… IP Route Commands - Cisco

What do these Cisco IOS commands do? Solutions | Experts

Nov 22, 2018 · Early of 2018, I got a chance to buy a Cisco Wireless Access Point with only $30, which is a great deal for AIR-LAP1142N-x-K9 – Dual-band Controller-based 802.11a/g/n. It is not 802.11ac ready AP, but as a replacement for my home wireless router, it is already enough. Since this device is enterprise product, the configuration is not that straightforward, even after read some Cisco documents this is the other "side" of your /30 outside interface, it should be fine ip forward-protocol nd! no ip http server no ip http secure-server! ip nat inside source list 1 interface GigabitEthernet0/0 overload! no service-routing capabilities-manager access-list 1 permit access-list 1 permit access int s0 ip access 101 in ip access 102 out no ip source-route the no ip source-route line is recommended by Cisco to help prevent other forms of spoofing. Also note that if you have Cisco IOS 10.3 or later then you can replace any instance of with the keyword any. -0500 -5 0 clock summer-time -0400 recurring no ip source-route no ip cef ip domain name ip name-server ip name-server dot11 pause-time 100 dot11 syslog Cisco Wireless IP Phone 8821 and 8821-EX Wireless LAN Deployment Guide Jun 11, 2012 · But this is a Layer 2 environment. What I needed was a layer 2 traceroute tool. Turns out Cisco does offer a Layer 2 traceroute utility for IOS on both the Cisco 7600 series routers and Catalyst 3560 series switches. It’s been around since 12.2(18) and you can use either MAC address or IP address to run the trace. The IP header source route option allows the source IP host to set a packet's route through the IP network. With IP source routing enabled, packets containing the source route option are forwarded in accordance with the specified router addresses contained in the header. Hi, There's a complex task to configure static nat with ip sla on cisco router 2951 Description: There're 2 ISPs (2 physical links to providers). Users access Internet through 1st ISP (dynamic NAT) and servers access internet through 2nd ISP (static nat + port forwarding). both servers and users are in the same network, connected via one router interface and have the same default gateway ip addr.