To share what I've learned !

In the above diagram , both hosts don't have default routes. But both are in the same /16 subnet. When host1 tries to ping host2 will it be able to ping ? Yes this behaviour due to the Proxy Arp feature. Note: Cisco by default enabled the proxy arp feature you have to disable it manually . Check the following Debug messages "debug arp" from the router. When the Arp request for 192.168.20.101 received on the router Fa0/1 it replies with its own mac address of fa0/1. (c200.03fc.0001)and vice versa *Mar 1 00:11:43.071: IP ARP: rcvd req src 192.168.12.154 00aa.00f4.6800, dst 192.168.20.101 FastEthernet0/1 *Mar 1 00:11:43.075: IP ARP: sent rep src 192.168.20.101 c200.03fc.0001,dst 192.168.12.154 00aa.00f4.6800 FastEthernet0/1 *Mar 1 00:13:13.067: IP ARP: rcvd req src 192.168.20.101 00aa.0041.1d00, dst 192.168.12.154 FastEthernet0/0 *Mar 1 00:13:13.067: IP ARP: sent rep src 192.168.12.154 c200.03fc.0000, dst 192.168.20.101 00aa.0041.1d00 FastEther...

 this blog we will look the PPP link's ip route / address negotiation . In the above diagram, there is not static routing / protocol implemented just serial interface with ppp encapsulation link brought up .   if you try to ping the R1 interface ip 192.168.100.1  from R2 interface ip 192.168.1.1 will it succeed ? R2#ping 192.168.100.1 Lets check the router interface: R1#show run int s1/0 Building configuration... Current configuration : 160 bytes ! interface Serial1/0 ip address 192.168.200.1 255.255.255.0 secondary ip address 192.168.100.1 255.255.255.0 encapsulation ppp serial restart-delay 0 R2#show run int s1/0 Building configuration... Current configuration : 110 bytes ! interface Serial1/0 ip address 192.168.1.1 255.255.255.254 encapsulation ppp serial restart-delay 0 end Answer is Yes you can ping. R2#ping 192.168.100.1 Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 192.168.100.1, ti...

Can we assign /31 address on the point to point link & save 50 % of ip address?  Answer is yes. R2(config)#int fa0/0 R2(config-if)#ip address 192.168.1.0 255.255.255.254 % Warning: use /31 mask on non point-to-point interface cautiously R4(config)#int fa0/0 R4(config-if)#ip address 192.168.1.1 255.255.255.254 % Warning: use /31 mask on non point-to-point interface cautiously Let’s try to ping :) R4#ping 192.168.1.0 Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 192.168.1.0, timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 1/2/4 ms Ok do we need privilege mode to ping ? no . R4> ping 192.168.1.0 Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 192.168.1.0, timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 1/2/4 ms Let’s check the ip route: R4#show ip route Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP D - EIGRP, EX - EIGRP...

After the release of the rootkit.com whole Mysql database (http://stfu.cc/rootkit_com_mysqlbackup_02_06_11.gz) 85000 users detail (if we remove the duplicate at least 50000 users) I searched my data obviously listed there.. :( Anyway i used to rotate my passwords and use lame passwords in the forums i feel safe. But after the breach the owners could advise the users of the group may be they don’t have the data now ? Some of the hashes i could reverse. I searched some Sri Lankan users around 30 users i could reverse some of the users password obviously my one too as reference ;). Hope dedicated crackers could use large rainbow table to reverse more of it I don’t wont to waste my time. One reverse hashing site: http://md5.thekaine.de/ ( if you have better sites please let me know) http://md5.my-addr.com/md5_decrypt-md5_cracker_online/md5_decoder_tool.php http://www.netmd5crack.com/cracker/ http://isc.sans.edu/tools/reversehash.html 1023 passwords are - "123456" :) 384 - passw...

One of the cool feature on Mikrotik queuing is Per Connection Queuing . we can equally distribute the bandwidth among Number of users.[1] This setup explores the per connection queuing in the congestion situation and how to utilize the priority queuing features. [Please note Mikrotik Queue lowest priority value have highest priority eg: queue priority 7 traffic gets highest preference over queue priority 8  ] In this test setup 192.168.92.50 and 51 given 512Kbps per connection queuing(PCQ) Priority 6 . 192.168.52 and 54 placed under 256Kbps PCQ (Priority 8) and further youtube users given 384Kbps irrespective to the queue they are currently placed ( FIFO) . 1) Bridge setup - " Don't forget to enable the bridge firewall :) " /interface bridge add admin-mac=00:00:00:00:00:00 ageing-time=5m arp=enabled auto-mac=yes comment="" disabled=no forward-delay=15s l2mtu=1522 \ max-message-age=20s mtu=1500 name=br_traffic_shaper priority=0x8000 protocol-mode=none...

I was trying some telnet coding on NET::TELNET and received some text as the response from mikrotik router. [m [36m/interface [m [m [36methernet when you see such a text file in your windows notepad editor (? ) ( i thought to replace this unwanted character :) ) what you will do ? after some googling i found this is the ANSI color code that supported by Linux terminals, if you do cat it will display correctly . windows there are some resources seems to be outdated anyone find better resources ? http://www.andre-simon.de/zip/download.html#ansifilter http://www.defacto2.net/nfo-files.cfm

cisco if the interface type is point to point we don't need to assign ip address related to RFC 1812 2.2.7 section : Related to this if the interface type is P2P we can assign same ip address to two interfaces. Serial1/0 192.168.1.1 YES manual up up Serial1/1 192.168.1.1 YES manual up up Ok if i ping 192.168.1.2 where it will go ? lets explore it .. Basic diagram R2 (s1/0)-- --(s1/0) R3 -- LO 192.168.6.1/32 R1#show ip route 192.168.1.2 Routing entry for 192.168.1.0/30 Known via "connected", distance 0, metric 0 (connected, via interface) Routing Descriptor Blocks: * directly connected, via Serial1/0 Route metric is 0, traffic share count is 1 directly connected, via Serial1/1 Route metric is 0, traffic share count is 1 so basically load sharing :) further more , R1#show ip cef 192.168.6.1 192.168.6.1/32 nexthop 192.168.1.2 Serial1/0 nexthop 192.168.1.2 Serial1/1 if...