2. 99.999 Reliability (5.39 ‘ per year)
Overview of reliability
Outside Network
Two different ISPs
Two BGP Routers – each connected to their respective ISP and to one another. Each router has told the neighboring routers that there are two ways out and back in. From the Core Network there are two links from the ASA 5510 Firewalls to each router.

3. Outside Network
Highnet 100MBPS
BGP Router
Primary
Two different ISPs
Access both routers
Routers use BGP
The routers tell everything to the ISP about their networks. The ISPs pass the information on to the other routers in the network
208… network
Lownet 10 MBPS
Secondary
Two different ISPs to one source is multi-homing
BGP Router

4. Outside Network
Highnet 100MBPS
BGP Router
Primary
Multi-homing
Both routers advertise the 208 … network range to the ISPs. The ISPs advertise the 208… network to the neighboring routers.
There are two ways in and out of this network.
208… network
Lownet 10 MBPS
Secondary
BGP Router

5. Outside Network
Highnet 100MBPS
BGP Router
Primary
If the primary link between the BGP router and Highnet ISP fails, the incoming traffic can use the secondary link (back up). The traffic from the Core Network is routed thru the joining link to the secondary router to access the ISP.
208… network
Lownet 10 MBPS
Secondary
BGP Router

6. Outside Network
Highnet 100MBPS
ASA
Stack
BGP Router
Primary
If the primary link between the BGP router and Highnet ISP fails, the incoming traffic can use the secondary link (back up).
208… network
How does the back up router know that it has to take over control. The primary BGP router uses SLA pings every 1 – 2 seconds to the ISP. No response from the ping, fail over to the primary router info to secondary router.
Lownet 10 MBPS
Secondary
IBGP Router

7. Core Network
Outside Network
Highnet 100MBPS
BGP Router
Primary
Core Switch Stack
ASA 5510
Stack
ASA is a fail over configuration (primary and secondary). Switches always pass traffic and no waiting for one to fail.
Lownet 10 MBPS
BGP Router
Access Points
Secondary
Wireless
Controller

8. Files
SAN
Server switch
stack
Core Network
WWW
VMWare
Servers
SQL
Access Points
Host switch stack
User
Phone
Printer
Wireless Controller