2.1 The Connected Globe

Question 1

Dynamic routing protocol classification

Answer 1

• Distance Vector (Routing Information Protocol, RIP)
• Link State (Open Shortest Path, OSPF)
• Path Vector (Border Gateway Protocol, BGP)

Question 2

Mechanisms to prevent RIP routing loops

Answer 2

• Split Horizon (no advertising back)
• Triggered updates (immediate)
• Route poisoning (15 hop limit)
• Holddown timers (unreachable)

Question 3

Internetworking model hierarchy

Answer 3

• Access (network connection)
• Distribution (compute-intensive routing and sw)
• Core (high-speed routing and sw)

Question 4

Basic DNS records types

Answer 4

• A (IPv4) or AAA (IPv6) (Address), domain to IP
• CNAME (Canonical Name), domain to another hostname
• MX (Mail Exchanger), Hostname of email server
• PTR (Pointer), Points to a CNAME.
• SOA (Start of Authority), authoritative info about DNS
• NS (Name Server), authoritative name server
• TXT (Text), text-based info.