Month: November 2017


OSI Stands for open system interconnection model.  This is reference or virtual model, you cannot see it , touch it ,but its exists conceptually just like electron, protons etc. OSI model is invented by ISO(International standard organization). ISO is non profit organization that defines several  standards. It is just like other standard e.g ISI mark,

Site to Site IPsec VPN

Topology Summary: To implement Flex VPN or IPSEC VPN the topology shown above. The motive is to make the reachability between LAN to LAN network i.e from to & vice versa. Currently we have configure simple connectivity in which R1 and R2 is reachable to each other via internet cloud. The basic requirement