Other

Question 1

IPV4 address format

Answer 1

A 32-bit sequence identifying a machine on
a network:
11000011 01010011 00001000 00011001
• Displayed as a four decimal sequence separated by a dot:
195 . 83 . 8 . 25

Question 2

IPV4 NAT

Answer 2

Network Address (NAT) provides another
workaround to public IP shortage but :
• Indirect connexion to Internet
• Complex access to internal services:
• Port redirections
• Proxies

Il retient l’adresse initiale grâce à l’information du port

Question 3

IPv4 Addresses allocation

Answer 3

Addresses allocation:
• Manually
• Automatically via DHCP
• Automatically through the “Automatic Private Internet Protocol
Addressing” mode (169.254.x.x)

Question 4

IPv4 Different addresses types

Answer 4

Different addresses types:
• Machines or unicast
• Network
• Broadcast
• Multicast

Question 5

IPv6

address format

Answer 5

A 128-bit sequence identifying a machine
on a network
0010101000000000 0001010001010000 0100000000000111 0000100000000110 0000000000000000
0000000000000000 0000000000000000 0001000000001111
• Displayed as an eight four-hex-digit sequence separated by a
colon
2a00:1450:4007:0806:0000:0000:0000:100f
• Simpliflied by following some rules
2a00:1450:4007:806::100f

Question 6

IPv6 : Address scopes

Answer 6

IPv6 addresses are grouped in scopes
• Based on prefixes
• Major prefixes :
• 2000::/3 : Global Scope
• FF00::/8 : Multicast
• FE80::/10 : Link Local

Question 7

IPv6 : Address allocations

Answer 7

IPv6 address allocation:
• Manually
• Automatically: StateLess Address Auto
Configuration (SLAAC)
• For the Link Local address
• For other scopes: based on router announcements
• Via DHCP(v6) : Statefull Mode
• Hybrid or mixed mode: SLAAC & DHCP

Question 8

IPv6 network interface activation

Answer 8

• IPv6 network interface activation:
• SLAAC address on link local scope
• Router discovery (RD sent to FF02::2) it is an router solicitation (RS), the routers are listening this path
• IPv6 router configuration defines what happens next
through Router Announcements (RA):
• Prefix announcement -> SLAAC based on the prefix
• Statefull flag set -> DHCP request

Question 9

IPv6 : other (main) differences

Answer 9

No more ARP
• Replaced by specific ICMPv6 modes (Neighbor
solicitations & announcements)
• No more broadcast traffic
• Multicast is (more) widely used
• Address duplicates auto-detection

Question 10

IPv6 : Different allocation for the interface ID

Adresse IPV6 détails

Answer 10

Adresse IPV6

64 premiers bits;
préfixe ex : 2000/3
préfixe glogal = FAI (fournisseur d’accès internet = n bits
préfix local : nb de sous-réseaux = 64-prefix-n

64 derniers bits : SLAAC = interface ID
Different allocation for the interface ID
• Given by the DHCP service
. Mix : SLAAC prefic then DHCP service request
SLACC :

• Random based
• MAC based :
mac address = 624 = 48 bits (6 blocs de deux hex
premier 24 bits de la mac address : 24 bits
0xFFFE : 16 bits
deuème 24 bits de la mac address : 24 bits

7 ème bit en partant de la gauche vaut 1 si MAC addresse unique

Question 11

Create new vlan cisco and name it

Answer 11

(config) vlan 10

(config-vlan) name Faculty/Staff

Question 12

Colonnes table de routage

Answer 12

Network, Masque, Gateway, Interface

Question 13

TCP démarrer une session

Answer 13

Three way Hand Shake :

Syn
Syn Hack
Hack

Question 14

Informations données par le DHCP

Answer 14

Ip,
DNS,
Masque,
Default Gateway