Hi Forum Admin

Just doing sims and I cannot get a ping to 192.18.1.1 to respond in this sim even though all appears OK?

could someone make me clear with this plz..
Slot time is the time for a signal to reach the farthest end and get a jam signal from there back .. for traditional 10mbps ethernet using coax cable max cable lebgth was 500m..so using max 4 repeaters total network length was 2500m..so two times it is 5000m..and with 2*10^8 as the propagation delay..
it would take 25microsec..but considering 3microsec delay/repeater it would be 4 repeaters*3microsec *2(for both direction) ie another 24microsec..total of approx 50 microsec..during which our station can transmit 500 bits..rounded off to nearest power of two..that would be 512 bits..
Now if that was the correct or approx correct calculation for 10mbps..
Consider this for std ethernet 100mbps..
100mbps uses utp cables..whose max length is about 100m..so using 4 repeaters thats 500 m..giving a total of 1000m both way..which takes 5microsec..using same signal speed..and during this time our station can send 500 bits again..so approx 512 bits.. so that makes the slot time in both the same .. but why don't we consider repeater delay here ?? or am i getting it wrong..if so plz correct me .. thanks in advance ..

needed help with this question ..hope someone would help ..
full-duplex transmission requires point-to-point link ,like we get by using switches.. but bridge ,which is quite similar to switches (except a few diff),usually connects two network segments ,which makes it a multi-point link.. but if a two-port bridge is used to connect single node on each port..Can it be used for full duplex communication ?? plz help..thanks in advance.

Hi people,

I have a question on Ext-ACL. Please help..

Users in IT Dept network (192.168.3.0) should not be able to ping or access KL Dept network (192.168.3.0) and vice versa.
Both IT Dept and KL Dept should be able to access the internet.

So my acl command is:
deny ip 192.168.3.0 0.0.0.255 host 192.168.3.0 eq icmp
deny ip 192.168.5.0 0.0.0.255 host 192.168.5.0 eq icmp
permit any any

Is my command correct?
A friend of time told me that, my command will block the respective network from accessing the internet and everything else as well?
Is it true?

Please help people! Urgent! Thanks!!! 

I had this doubt while studying about bridges and switches..Hope someone would help me.
A bridge helps divide the collision domain by dividing an otherwise single network into two or more network segments,so that each network segment acts as a separate collision domain.If two or more devices from different segments intend to send data to nodes which are in the same segment ,does that result in a collision at the receiver segment ??
and similarly I read that there's no collision in a full-duplex switched system,so there's no need for collision handling techniques.. What if two or more nodes in such a system,send data to a same node..does that result in a collision at the receiver side ??
Hope to get help from someone..thanks in advance.

I am completing Exploration by Cisco Network Academy.
But I am not sure to take CCNA or ICND1/ICND2.

My trouble to make decision is topics in Exploration are not structured to match the syllabus of ICND1/2
I have to pick and match topics to ICND1/2.
However, taking single exam CCNA seems to have a lot to remember, the risk is higher on one go.

Can some share some thoughts, CCNA or ICND1/2 easier to pass?

Each time you pass a Professional level exam, your active CCNA certification automatically recertifies for an additional 3 years period.

The Professional level exams (BSCI, BCMSN, Composite, etc) have a validity period of 3 years. So to earn your CCNP, you must complete all required CCNP exams within 3 years of taking your first CCNP exam.

Once you complete all required CCNP exams (within 3 years), your CCNP status will be active for 3 years beginning with the last test you took.

Hi all,

This is extracted from my ICND 1 text book.

I?m unclear what the 3 bullet points as below mean. Can I request some explanation how the destination IP addresses match all the routes?

Thank you in advanced.

Example 15-2 show ip route Command with Overlapping Routes

R1#show ip route rip
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route

Gateway of last resort is not set

172.16.0.0/16 is variably subnetted, 5 subnets, 4 masks
R 172.16.1.1/32 [120/1] via 172.16.25.2, 00:00:04, Serial0/1/1
R 172.16.1.0/24 [120/2] via 172.16.25.129, 00:00:09, Serial0/1/0
R 172.16.0.0/22 [120/1] via 172.16.25.2, 00:00:04, Serial0/1/1
R 172.16.0.0/16 [120/2] via 172.16.25.129, 00:00:09, Serial0/1/0
R 0.0.0.0/0 [120/3] via 172.16.25.129, 00:00:09, Serial0/1/0
R1#show ip route 172.16.4.3
Routing entry for 172.16.0.0/16
Known via "rip", distance 120, metric 2
Redistributing via rip
Last update from 172.16.25.129 on Serial0/1/0, 00:00:19 ago
Routing Descriptor Blocks:
* 172.16.25.129, from 172.16.25.129, 00:00:19 ago, via Serial0/1/0
Route metric is 2, traffic share count is 1

For the exam, to find the matching route, all you need to know is the destination IP address
of the packet and the router?s IP routing table. By examining each subnet and mask in the routing table, you can determine the range of IP addresses in each subnet. Then, you can compare the packet?s destination to the ranges of addresses, and find all matching routes.
In cases where a particular destination IP address falls within the IP address range for multiple routes, then you pick the route with the longest prefix length. In this case:

■ Destination address 172.16.1.1 matches all five routes, but the host route for specific
IP address 172.16.1.1, prefix length /32, has the longest prefix length.

■ Destination address 172.16.1.2 matches four of the routes (all except the host route for
172.16.1.1), but the route to 172.16.1.0/24 has the longest prefix.

■ Destination address 172.16.2.2 matches the last three routes listed in R1?s routing table
in the example, with the route for 172.16.0.0/22 having the longest prefix length.

■ Destination address 172.16.4.3 matches the last two routes listed in R1?s routing table in the example, with the route for 172.16.0.0/16 having the longest prefix length.

Finally, note the output of the show ip route 172.16.4.3 command at the end of Example
15-2. This command shows which route the router would match to reach IP address
172.16.4.3?a very handy command for both real life and for Sim questions on the exams.
In this case, a packet sent to IP address 172.16.4.3 would match the route for the entire
Class B network 172.16.0.0/16, as highlighted near the end of the example.

Hi,

  I'm currently taking CCNA courses but was recently stuck with STP. To be exact, I'm not stuck with what it does, just some protocols related to it.

  So far, I understand that RSTP is much faster than STP. PVST+ is composed of PortFast, BackboneFast, and UplinkFast. But then, I was stuck by the relationship between RSTP, PVST+, and PVRST+. The review book I'm using (CCNA Exam Cram) tells me that "A Cisco Catalyst switch running PVST+ or PVRST+ maintains an instance of spanning tree for each active VLAN that is configured on the switch.", which I currently have no idea what it means. Please guide me out of this mess, thanks.

  Also, the Trunking part is kind of ambiguous, so to speak. What exactly is a trunk? is it just a protocol (that would be 802.1Q or ISL, right?) or hardware (cross-over cable?)?

I just passed the composite (640-802) exam with a score of 874 (not a good score). I missed  (something really simple) out on a simulation (NAT), and if I had successfully finished it , then my score might have been a little over 900. Never the less, H2P has been a great help!

Thanks to everyone who had help me on this forum.