CCIE R&S Advanced Technologies Class v4.5

Transcript

1	Introduction	0h 43m
2	Using the Cisco Documentation	0h 52m
3	Ethernet Overview, Layer 2 Switchports, Trunking, ISL, 802.1q, DTP	0h 47m
4	VTP, VTP Authentication, VTP Pruning	1h 02m
5	VTP Prune Eligible List, VTP Transparent, VTP Troubleshooting, Trunk Allowed List, Extended VLANs	0h 48m
6	VLAN and VTP Review	0h 19m
7	SVIs, Native Routed Interfaces, Router-on-a-Stick	0h 46m
8	Layer 2 EtherChannel, EtherChannel Load Balancing, Layer 3 EtherChannel	0h 57m
9	802.1q Tunneling, Layer 2 Protocol Tunneling, EtherChannel over 802.1q Tunneling	1h 03m
10	STP Root Bridge Election, STP Root Port Election, STP Designated Port Election, STP Priority, STP Cost, STP Port-Priority	1h 46m
11	STP Review	0h 12m
12	STP Timers, STP PortFast	0h 34m
13	STP UplinkFast	0h 11m
14	STP BackboneFast	0h 12m
15	STP BPDU Filter	0h 13m
16	STP BPDU Guard	0h 11m
17	STP Root Guard	0h 11m
18	STP Loop Guard, Unidirectional Link Detection (UDLD)	0h 11m
19	Multiple Spanning-Tree Protocol (MST)	0h 40m
20	Rapid Spanning-Tree Protocol (RSTP), Rapid-PVST	0h 18m
21	MST with Multiple Regions	0h 33m
22	Flex Links	0h 16m
23	Frame Relay	0h 39m
24	Frame Relay Configuration Part 1	0h 34m
25	Frame Relay Configuration Part 2	0h 41m
26	Frame Relay Switching	0h 27m
27	Back-to-Back Frame Relay	0h 08m
28	Frame-Relay End-to-End Keepalives	0h 18m
29	PPP, PPP PAP Authentication, PPP CHAP Authentication	0h 59m
30	PPPoFR, PPPoE	0h 40m
31	Transparent Bridging, IRB	0h 32m
32	Fallback Bridging	0h 14m
33	IP Routing Overview, Switching Paths, Static Routing	0h 42m
34	Static Routing Examples	0h 25m
35	IP Default-Gateway, IP Default-Network	0h 14m
36	On-Demand Routing (ODR)	0h 07m
37	Floating Static Routes	0h 10m
38	Backup Interface	0h 29m
39	Enhanced Object Tracking, IP SLA, Reliable Static Routing	0h 21m
40	Policy Routing	0h 43m
41	GRE Tunneling, GRE Recursive Routing Errors	0h 27m
42	Reliable Backup Interface with GRE	0h 25m
43	RIP Overview, RIP Versions, RIP Auto-Summary	0h 48m
44	RIP Split-Horizon, RIP Timers	0h 22m
45	RIP Broadcast Updates, IP Directed Broadcast, IP Broadcast-Address, Smurf Attacks, Fraggle Attacks	0h 16m
46	RIP Unicast Updates	0h 03m
47	RIP Offset-List	0h 18m
48	RIP Authentication	0h 11m
49	RIP Summarization	0h 10m
50	Prefix-Lists, RIP Distribute-List Filtering, RIP Administrative Distance Filtering	0h 48m
51	RIP Default Routing, RIP Conditional Default Routing	0h 18m
52	RIP Triggered, RIP Validate Update Source,	0h 12m
53	EIGRP Overview	0h 29m
54	EIGRP Auto-Summary	0h 07m
55	EIGRP Split-Horizon	0h 11m
56	EIGRP Update Types, EIGRP Neighbor, EIGRP Passive-Interface	0h 24m
57	EIGRP Hello-Interval, EIGRP Hold-Time	0h 05m
58	EIGRP Authentication	0h 11m
59	EIGRP Time Based Authentication	0h 25m
60	EIGRP Path Selection, EIGRP Metric Weights, EIGRP Traffic Engineering	0h 47m
61	EIGRP Unequal Cost Load Balancing, EIGRP Variance	0h 19m
62	EIGRP QUERY, EIGRP Summarization, EIGRP Leak-Map	0h 28m
63	EIGRP Stub Router Advertisement	0h 22m
64	EIGRP Default Routing	0h 13m
65	EIGRP Route Filtering	0h 11m
66	EIGRP Router-ID	0h 07m
67	Miscellaneous EIGRP Features	0h 02m
68	OSPF Overview	0h 27m
69	Establishing OSPF Adjacencies, Understanding the OSPF Database	0h 43m
70	OSPF Network Type Broadcast, OSPF DR/BDR Election, OSPF over NBMA, OSPF Network Type Non-Broadcast and Point-to-Multipoint	0h 56m
71	OSPF Network Type Point-to-Point, OSPF Network Type Mismatch	0h 13m
72	OSPF Network Type Point-to-Multipoint Non-Broadcast, OSPF Per Neighbor Cost	0h 17m
73	OSPF Network Type Loopback	0h 02m
74	OSPF Path Selection	0h 27m
75	OSPF Convergence Timers	0h 09m
76	OSPF Authentication	0h 12m
77	OSPF Summarization	0h 32m
78	OSPF Stub Areas, OSPF Totally Stubby Areas, OSPF NSSAs, OSPF Totally NSSAs	0h 40m
79	Controlling OSPF NSSA Redistribution	0h 02m
80	OSPF Type 7 to 5 Translator Election, OSPF LSA Type 3 Filter, OSPF Forwarding Address Suppression	0h 24m
81	Route Redistribution Overview	0h 36m
82	Route Redistribution Configuration & Verification, Connected Redistribution	0h 22m
83	OSPF External Path Selection, TCL PING Scripting	0h 33m
84	Routing Loops Overview, EIGRP Route Loop Prevention	0h 55m
85	Metric Based Routing Loops, Route Tagging	0h 46m
86	Administrative Distance Based Routing Loops, Debug IP Routing, IP Route Profile	0h 58m
87	BGP Overview, BGP Peering Types	0h 51m
88	Establishing BGP Peerings, EBGP Multihop, BGP Neighbor Disable Connected Check, BGP TTL Security	0h 49m
89	BGP 4-Byte ASNs	0h 20m
90	BGP Local AS, BGP Peer Groups	0h 30m
91	BGP Next-Hop Self, BGP Next-Hop Processing	0h 30m
92	BGP Route Reflectors	0h 37m
93	Large Scale BGP Route Reflectors with Clusters	0h 34m
94	BGP Confederation	0h 37m
95	BGP NLRI Advertisements, BGP Network Statement, BGP Redistribution	0h 43m
96	BGP Aggregation, BGP Aggregation & Summary-Only, BGP Aggregation & Unsuppress-Map	0h 46m
97	BGP Origin, BGP Aggregation & AS-Set, BGP Aggregation & Advertise-Map	0h 22m
98	BGP Conditional Route Injection	0h 21m
99	BGP Bestpath Selection, BGP Multipath, BGP Weight	0h 53m
100	BGP Local Preference, BGP Local Preference and Communities, BGP AS-Path Prepending,	0h 30m
101	BGP MED, BGP MED Missing As Worst, BGP Deterministic MED	0h 17m
102	BGP Communites, BGP Regular Expressions	0h 43m
103	BGP Filtering, BGP Convergence Timers, BGP Default Routing, Miscellaneous BGP Features	0h 24m
104	MPLS Overview, MPLS Label Distribution Protocol (LDP)	1h 05m
105	MPLS Tunnels, MPLS Penultimate Hop Popping (PHP)	0h 40m
106	MPLS Layer 3 VPNs Overview, VRF Lite	0h 36m
107	MPLS Layer 3 VPNs and VPNv4 BGP	1h 08m
108	MPLS Layer 3 VPN Verification & Troubleshooting	0h 49m
109	MPLS Layer 3 VPN OSPF PE-CE Routing Overview	0h 06m
110	MPLS Layer 3 VPN OSPF PE-CE Routing Path Selection & Sham-Links	2h 01m
111	MPLS Layer 3 VPN OSPF PE-CE Routing Loop Prevention & Down-Bit, OSPF Capability VRF-Lite	0h 40m
112	IPv6 Overview, IPv6 ICMPv6 ND, IPv6 over NBMA	0h 44m
113	IPv6 Routing Overview, IPv6 Static Routing	0h 28m
114	IPv6 RIPng	0h 20m
115	IPv6 EIGRPv6	0h 09m
116	IPv6 OSPFv3	0h 31m
117	MP-BGP for IPv6	0h 26m
118	IPv6 Tunneling	1h 13m
119	Multicast Overview, IGMP	0h 34m
120	PIM Overview	0h 18m
121	PIM Dense Mode	1h 03m
122	PIM Sparse Mode	0h 30m
123	PIM Sparse Mode Configuration	0h 36m
124	PIM Sparse Mode RPF & RP Troubleshooting	0h 27m
125	Auto-RP, Multicast over GRE Tunnels	0h 53m
126	Bootstrap Router (BSR), Bidirectional PIM, Source Specific Multicast (SSM)	0h 40m
127	MSDP, Anycast RP	0h 27m
128	IPv6 Multicast Routing	0h 24m
129	QoS Overview, IntServ QoS, DiffServ QoS, IP Precedence, DSCP, MQC, HQF	0h 41m
130	MQC Classification	0h 44m
131	FIFO, FQ, WFQ, CBWFQ, HQF	0h 50m
132	LLQ	0h 23m
133	WRED	0h 31m
134	Traffic Shaping, Traffic Policing	0h 40m
135	Frame Relay Traffic Shaping (FRTS)	0h 33m
136	RSVP	0h 07m
137	Catalyst 3560 QoS	1h 00m
138	IOS Security Overview, Access Lists (ACLs)	0h 58m
139	Time Based ACLs, Dynamic ACLs	0h 33m
140	Reflexive ACLs	0h 21m
141	TCP Intercept, Content Based Access Control (CBAC)	0h 34m
142	Zone Based Policy Firewall (ZBPF)	1h 09m
143	AAA, Local Authentication, Local Authorization, Role Based CLI Access	0h 43m
144	Port Security, Static CAM Entries, Storm Control, 802.1X Authentication, PACLs, RACLs, VLAN Access Maps (VACLs)	0h 48m
145	DHCP Snooping, Dynamic ARP Inspection (DAI), IP Source Guard	0h 12m
146	Protected Ports, Private VLANs	0h 25m
147	IP Services Overview, HSRP	1h 10m
148	VRRP, GLBP	0h 28m
149	NAT	0h 42m
150	DHCP, DNS	0h 30m
151	NetFlow	0h 09m
152	WCCP, Miscellaneous IP Services	0h 06m
153	System Management Overview, NTP, NTP Authentication	0h 24m
154	SNMP, RMON	0h 38m
155	Syslog, Telnet, SSH, Banners	0h 21m
156	EEM Scripting, Miscellaneous System Management	0h 26m
Total Duration		81h 42m

Slides - Diagrams

Slides - Introduction

Slides - Ethernet Switching

Slides - Advanced Ethernet Switching

Slides - Frame Relay

Slides - PPP

Slides - Transport Bridging

Slides - Redistribution

Slides - IOS Security

Slides - Layer 2 Security

Slides - IP Services

Slides - System Management

0:00:11	Our next topic here is authentication in OSPF,
0:00:15	which can get kind of confusing the way that it is documented.
0:00:20	And the difference between area authentication versus interface authentication.
0:00:26	Now, some of the descriptions of this...
0:00:29	say that "OSPF supports two different type of authentication which is at the interface level and at the area level."
0:00:35	Technically, there's no difference between them.
0:00:38	Okay, in reality, OSPF supports 3 different types of authentication, which is null, or no authentication,
0:00:45	clear text, and MD-5.
0:00:48	At a packet level format,
0:00:51	there's no difference in the authentication types whether you have it enable globally under the process,
0:00:57	or directly at the interface level.
0:01:00	The only difference is that if you enable it under the process,
0:01:04	it's going to automatically apply to any interfaces within that area.
0:01:09	So, if I were to say Area Zero Authentication,
0:01:13	it means that every link that is in area zero is going to have type 1 authentication applied to it.
0:01:20	This would be the exact same implementation if I were to go to each of the link levels,
0:01:24	and say, IP OSPF Authentication.
0:01:28	So, regardless of how we configure it,
0:01:31	we can verify this by looking at the Show IP OSPF Interface.
0:01:35	It's gonna tell us what type of authentication has been configured.
0:01:38	Now, for the actual password, whether this is a clear text key or an MD-5 key,
0:01:44	this is always gonna be configured at the link level.
0:01:47	With either the IP OSPF authentication key,
0:01:50	for clear text, or the IP OSPF message digest key for MD-5.
0:01:57	Also a key point just notice here
0:01:59	that a virtual link is an area zero interface.
0:02:05	So, if we're doing authentication on all interface in area zero,
0:02:10	and sometime down the road, we configure a virtual link,
0:02:13	it means that the virtual link will automatically inherit that type of authentication.
0:02:19	Now, it can get kind of strange though
0:02:22	if you inherit the authentication type but do not configure a key.
0:02:28	As long as the neighbors agree on what the authentication type is
0:02:32	you can actually use a null value for the password.
0:02:36	Now, what I mean by this, if we were to go to...
0:02:40	Let's say the link between router 5 and switch 2,
0:02:43	and on both of these neighbors say, IP OSPF Authentication Message Digest.
0:02:48	They would be running MD-5 Authentication,
0:02:51	but they would be doing it without a password.
0:02:54	So, they would essentially be creating the hash value based on just the solve value, based on no password.
0:03:01	But as long as the end result matches, then, the authentication is successful.
0:03:04	And you can proceed on with the adjacency.
0:03:09	The possible problem could be though within the scope of the lab exam,
0:03:13	if we had a question that says something like,
0:03:16	"Run clear text authentication on every interface in area zero using the password CISCO."
0:03:23	If I have a virtual link then, it would imply that I need the password CISCO,
0:03:27	and the clear text authentication on that link.
0:03:31	So, we'll come back to this later when we get into virtual links in more detail,
0:03:36	but it is an important point to know that the virtual link is in area zero interface.
0:03:40	So first, let's look at an example between router 5 and switch 2,
0:03:45	where we are doing clear text authentication.
0:03:49	On router 5, if we look at the Show IP OSPF Interface Brief,
0:03:54	this link that connects to switch 2 in area 2.
0:03:58	This means that I effectively have two different ways I can enable the authentication.
0:04:03	I could go directly to the link level,
0:04:06	and say IP OSPF Authentication.
0:04:09	Or I could go under the process level and say Area 2 Authentication.
0:04:13	In either case, when I look at the result of Show IP OSPF Interface Fa0/0,
0:04:21	we should see all the way at the bottom that it says "Clear text authentication is enabled."
0:04:25	or "MD-5 authentication is enabled."
0:04:29	So on router 5, if we say under the OSPF process,
0:04:32	Area 2 Authentication.
0:04:36	The other option would be for message digest, which is MD-5.
0:04:43	On switch 2, if we now look at the Debug IP OSPF Adjacency,
0:04:49	we should see that any of the new updates that are coming in from router 5
0:04:55	will be discarded because there's a mismatch on the authentication type.
0:05:00	Where in this case, switch 2 is saying, "I use type zero,
0:05:05	which is null authentication."
0:05:09	Where router 5 is trying to use type 1, which is clear text.
0:05:15	So, this is different that a mismatch in the authentication key,
0:05:20	which would be the password.
0:05:21	This is a mismatch in the type of authentication.
0:05:26	So, at the link level of switch 2,
0:05:28	if we were to say IP OSPF Authentication,
0:05:33	this is turning the process on.
0:05:36	Even though we don't have a password configured,
0:05:39	they're technically now doing clear text authentication with no key.
0:05:46	If we Show IP OSPF Interface VLAN 58,
0:05:51	we see that simple password authentication is enabled.
0:05:56	Now ideally, you would not want to do
0:05:59	this type of configuration where you're just enabling the type of authentication but not actually configuring a key.
0:06:05	Because as we saw from the debug,
0:06:08	we can tell from the OSPF hello what type of authentication the remote neighbor is running.
0:06:13	Then, if someone were to turn it on with no password,
0:06:16	they could insert false routing information into the network.
0:06:19	And that's ideally what we're trying to prevent with this authentication.
0:06:22	We don't want someone adding or withdrawing LSA information
0:06:26	unless their legitimate router is part of the routing topology.
0:06:31	So normally, at the link level, we would say, "The IP OSPF authentication key is...
0:06:37	whatever the password is, let's say CISCO in this case."
0:06:41	And then of course, this would have to match on both sides.
0:06:46	So on router 5, we'll also say, "The key is CISCO."
0:06:51	In some versions of IOS, we could run into the same problem that we did before with the key chain
0:06:57	that if you define the authentication key,
0:07:02	and then put a space after it,
0:07:07	when we Show IP OSPF... Or not Show IP OSPF, Show Run Interface Fast Ethernet 0/0,
0:07:15	when we select this,
0:07:19	we can see there is a white space after the password.
0:07:25	So, for the vast majority of versions, the IOS will take white spaces as characters for passwords.
0:07:33	But you can see this from highlighting the output.
0:07:37	Unfortunately, there's no other show command like there is for the Show Key Chain
0:07:41	that's gonna tell us that's the problem with the configuration.
0:07:50	So, at this interface, it should be...
0:07:53	capital CISCO with no spaces after it.
0:08:03	Now, for MD-5 authentication,
0:08:05	it's essentially gonna be the same.
0:08:07	Let's say that on router 5, we now wanna do MD-5 authentication of the link that goes to router 4.
0:08:15	On router 5's side, we could say on this link level,
0:08:19	IP OSPF...
0:08:22	Authentication is using message digest.
0:08:26	The IP OSPF message digest key...
0:08:30	will be a key number 10 using MD-5, and the password is...
0:08:37	MD5 key.
0:08:44	Just like in EIGRP, the key number value does have to match,
0:08:49	because it is included in the update.
0:08:53	We'll see that for doing multiple keys in the interface, and doing key rotation for OSPF,
0:08:58	we do this by putting multiple key numbers on there
0:09:03	wait until we start using the new value,
0:09:05	and then remove the old value.
0:09:09	So, we see we'd lost the adjacency to router 4 now because it's not using the same type of authentication.
0:09:15	If we were to go to router 4 and then, under the OSPF process,
0:09:19	say Area Zero Authentication Message Digest.
0:09:26	This is going to enable the process in all interface in area zero.
0:09:31	Then, at the link level,
0:09:34	we would specify what is the key.
0:09:38	If we look at the Debug IP OSPF Adjacency,
0:09:44	we should then see on the frame-relay interface,
0:09:49	we are using type 2 authentication, which is MD-5.
0:09:54	The other side is doing nothing, which is type 0.
0:09:57	So, we will loose the adjacency to router 5 over the frame-relay.
0:10:04	Also, we could see we're using key number zero on that link.
0:10:08	For the point-to-point link, we're using key number 10.
0:10:12	That's the one that we defined on the interface.
0:10:16	Now, in this type of configuration where on router 4,
0:10:20	we have MD-5 authentication configured on both interface in area zero.
0:10:29	And we did this again by using the process level command area zero authentication message digest.
0:10:36	We could now selectively come back,
0:10:39	and change the authentication on a per-link basis
0:10:43	by overriding it at the link level.
0:10:48	This would be the case where on router 4,
0:10:51	we could say, on the frame-relay that the IP OSPF authentication...
0:10:57	is null.
0:11:01	This now reverts us from type 2 authentication, which is MD-5
0:11:07	back to type zero authentication, which is null.
0:11:12	So, if we now look at the Show IP OSPF Interface,
0:11:16	we'll see that on the point-to-point link,
0:11:19	we're doing MD-5 authentication,
0:11:23	and we're using key number 10.
0:11:27	For the frame-relay, we're not doing any authentication.
0:11:33	So, even though under the process level, we said...
0:11:38	Area Zero Authentication Message Digest.
0:11:42	This is not applying to serial 0/0/0,
0:11:46	because I then overrode this configuration with the more specific level interface command.
0:11:52	So again, the key point for this is that there is no difference
0:11:55	from a packet level point of view
0:11:57	whether the authentication is configured on the interface level or under the process level.
0:12:03	The process level is simply doing it on multiple interfaces at the same time.
0:12:07	In either case, the actual authentication key always goes on the link.

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CCIE R&S Advanced Technologies Class v4.5
Title:	CCIE R&S Advanced Technologies Class v4.5
Duration:	81h 42m
The CCIE Routing & Switching Advanced Technologies Class is the first step in understanding CCIE level technologies and is a companion to the Advanced Technologies Lab Workbook. Each technology you need to know for the CCIE Routing & Switching lab will be described in detail using an instructor led hands on demonstration. The class consists of over 80 hours of in depth explanations and examples.
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