Chapter 3 - VLANS CCNA pot

Chapter 3 - VLANS Chapter 3 VLANS CCNA Exploration 4.0 1 Objectives • Explain the role of VLANs in a network. • Ex p lain the role of trunkin g VLANs in a network. pg • Explain the role of trunking VLANs in a network. • Troubleshoot the common software or hardware configuration problems associated with VLANs on switches in a network topology. Học viện mạng Bach Khoa - Website: www.bkacad.com 2 Role of VLANS • One of the contributing technologies to excellent network performance is the separation of large broadcast domains into smaller ones with VLANs. • Smaller broadcast domains limit the number of devices participating in broadcasts and allow devices to be participating in broadcasts and allow devices to be separated into functional groupings, such as database services for an accounting department and high-speed dt t f f i i d t t d a t a t rans f er f or an eng i neer i ng d epar t men t . Học viện mạng Bach Khoa - Website: www.bkacad.com 3 Before VLANS 1 building • 1 building -> OK • Man y buildin g -> NOT OK Many building yg – IT department wants to ensure that student computers all share the same security features and bandwidth controls. How can the network accommodate the shared needs of the geographically separated departments? Do you create a large LAN and wire each separated departments? Do you create a large LAN and wire each department together? – It would be great to group the people with the resources they use regardless of their geographic location, and it would make it easier to manage their specific security and bandwidth needs Học viện mạng Bach Khoa - Website: www.bkacad.com 4 to manage their specific security and bandwidth needs . VLAN overview • A VLAN allows a network administrator to create groups of logically networked devices that act as if they are on their own independent network • These VLANs allow the network administrator to implement Học viện mạng Bach Khoa - Website: www.bkacad.com 5 These VLANs allow the network administrator to implement access and security policies to particular groups of users. VLANS details • A VLAN is a broadcast domain created by one or more A VLAN is a broadcast domain created by one or more switches. • The network design above creates three separate bdtd i Học viện mạng Bach Khoa - Website: www.bkacad.com 6 b roa d cas t d oma i ns. Without VLANs – No Broadcast Control ARP Request Switch 1 172.30.1.21 255.255.255.0 172.30.2.12 255.255.255.0 172.30.2.10 255 255 255 0 172.30.1.23 255 255 255 0 No VLANs y Same as a single VLAN y Two Subnets 255 . 255 . 255 . 0 255 . 255 . 255 . 0 y Two Subnets • Without VLANs, the ARP Request would be seen by all hosts. • Again consuming unnecessary network bandwidth and host processing Học viện mạng Bach Khoa - Website: www.bkacad.com 7 Again , consuming unnecessary network bandwidth and host processing cycles. With VLANs – Broadcast Control Switch Port: VLAN ID ARP Request Switch 1 172.30.1.21 255.255.255.0 VLAN 1 172.30.2.12 255.255.255.0 VLAN 2 172.30.2.10 255 255 255 0 172.30.1.23 255 255 255 0 Two VLANs Two Subnets 255 . 255 . 255 . 0 VLAN 2 255 . 255 . 255 . 0 VLAN 1 1 2 3 4 5 6 . 1 2 1 2 2 1 . Port VLAN y Two Subnets Học viện mạng Bach Khoa - Website: www.bkacad.com 8 Benefit of VLANS Học viện mạng Bach Khoa - Website: www.bkacad.com 9 VLAN ID Học viện mạng Bach Khoa - Website: www.bkacad.com 10 [...]... mạng Bach Khoa - Website: www.bkacad.com 28 Trunking mode Học viện mạng Bach Khoa - Website: www.bkacad.com 29 Configure VLAN and Trunking • Add VLAN Học viện mạng Bach Khoa - Website: www.bkacad.com 30 Assign VLAN to port Học viện mạng Bach Khoa - Website: www.bkacad.com 31 Configuring Ranges of VLANs vlan 3 SydneySwitch(config)#interface range fastethernet 0/8 - 12 SydneySwitch(config-if)#switchport... access vlan 3 SydneySwitch(config-if)#exit Học viện mạng Bach Khoa - Website: www.bkacad.com 32 Verify VLAN • • • • Show vlan Show vlan brief Show interface vlan 2 Show interface fa0/18 switchport Học viện mạng Bach Khoa - Website: www.bkacad.com 33 Delete Vlan • • No vlan Delete flash:vlan.dat Học viện mạng Bach Khoa - Website: www.bkacad.com 34 Configure Trunk link Học viện mạng Bach Khoa - Website:... mạng Bach Khoa - Website: www.bkacad.com 18 Voice VLAN Học viện mạng Bach Khoa - Website: www.bkacad.com 19 Types of traffic Học viện mạng Bach Khoa - Website: www.bkacad.com 20 Types of traffic Học viện mạng Bach Khoa - Website: www.bkacad.com 21 Types of traffic Học viện mạng Bach Khoa - Website: www.bkacad.com 22 Types of traffic Học viện mạng Bach Khoa - Website: www.bkacad.com 23 Switch port membership... field Tag control information field – 3 bits of user priority - Used by the 802.1p standard, which specifies how to provide expedited transmission of Layer 2 frames A description of the IEEE 802.1p is beyond the scope of this course; however, you learned a little about it earlier in the discussion on voice VLANs VLANs – 1 bit of Canonical Format Identifier (CFI) - Enables Token Ring frames to be carried... Trunking will be discussed in the next chapter Học viện mạng Bach Khoa - Website: www.bkacad.com 12 Học viện mạng Bach Khoa - Website: www.bkacad.com 13 Types of VLAN • Data VLAN: A data VLAN is a VLAN that is configured to carry only user-generated traffic Học viện mạng Bach Khoa - Website: www.bkacad.com 14 Types of VLAN • Default VLAN: – All switch ports become a member of the default VLAN after the... mạng Bach Khoa - Website: www.bkacad.com 11 VLAN Tagging 802.10 • • • • There are two major methods of frame tagging Cisco proprietary Inter tagging, InterSwitch Link (ISL) and IEEE 802.1Q ISL used to be the most common, but is now being replaced by 802.1Q gg g frame tagging Cisco recommends using 802.1Q VLAN Tagging and Trunking will be discussed in the next chapter Học viện mạng Bach Khoa - Website:... Identifier (CFI) - Enables Token Ring frames to be carried across Ethernet links easily – 12 bits of VLAN ID (VID) - VLAN identification numbers; supports up to 4096 VLAN IDs FCS field Học viện mạng Bach Khoa - Website: www.bkacad.com 26 Native Vlan and 802.1q Học viện mạng Bach Khoa - Website: www.bkacad.com 27 Trunking mode • The trunking modes available in Fast Ethernet and Gigabit Ethernet switchport... Delete Vlan • • No vlan Delete flash:vlan.dat Học viện mạng Bach Khoa - Website: www.bkacad.com 34 Configure Trunk link Học viện mạng Bach Khoa - Website: www.bkacad.com 35 Common Problem Học viện mạng Bach Khoa - Website: www.bkacad.com 36 ... Học viện mạng Bach Khoa - Website: www.bkacad.com 22 Types of traffic Học viện mạng Bach Khoa - Website: www.bkacad.com 23 Switch port membership Học viện mạng Bach Khoa - Website: www.bkacad.com 24 VLAN Trunk Học viện mạng Bach Khoa - Website: www.bkacad.com 25 802.1Q tagging • • • EtherType field – Set to the hexadecimal value of 0x8100 This value is called the tag p g protocol ID ( (TPID) value With... address and subnet mask A switch can be managed via HTTP, Telnet, SSH, or SNMP Học viện mạng Bach Khoa - Website: www.bkacad.com 16 Types of VLAN • Native VLAN: – A native VLAN is assigned to an 802.1Q trunk port – A 802 1Q trunk port supports traffic coming f An 802.1Q t k t t t ffi i from many VLANs (tagged traffic) as well as traffic that does not come from a VLAN (untagged traffic) – The 802.1Q . Chapter 3 - VLANS Chapter 3 VLANS CCNA Exploration 4.0 1 Objectives • Explain the role of VLANs in a network. • Ex p lain the role of trunkin g VLANs in a network. pg •. Port: VLAN ID ARP Request Switch 1 172 .30 .1.21 255.255.255.0 VLAN 1 172 .30 .2.12 255.255.255.0 VLAN 2 172 .30 .2.10 255 255 255 0 172 .30 .1. 23 255 255 255 0 Two VLANs Two Subnets 255 . 255 . 255 . 0 VLAN. Bach Khoa - Website: www.bkacad.com 6 b roa d cas t d oma i ns. Without VLANs – No Broadcast Control ARP Request Switch 1 172 .30 .1.21 255.255.255.0 172 .30 .2.12 255.255.255.0 172 .30 .2.10 255