RSA has been invented in 1977 and till that time everyone things that encryption/decryption can be done only with one symetric key. As header says this is public key cryptosystem, so we gonna have two keys for encryption / decryption and that is public key and private key. I know about this setup so lets Full Article…
Search the Wiki
Viewing 101 to 110 of 151 items
HMAC
Hash-based message authentication code, or HMAC, is an important building block for proving that data transmitted between the components of a system has not been tampered with. HMAC is a widely used cryptographic technology. I recently came across its use in an RFID system. Perhaps the most common use of HMAC is in TLS—Transport Layer Full Article…
Komentáře nejsou povolené u textu s názvem HMAC
ELAM examples & commands
In this example a host on Vlan10 (10.1.1.101) port Eth6/4 sends an ICMP request to a host also on Vlan10 (10.1.1.102) off port Eth6/3. We will use ELAM to capture this single packet between the hosts. It’s important to remember that ELAM allows us to capture a single frame. To perform an ELAM on Full Article…
Komentáře nejsou povolené u textu s názvem ELAM examples & commands
Basic ELAM guide
ELAM (Embedded Logic Analyzer Module) is an engineering tool that gives us the ability to look inside Cisco ASICs and understand how a packet is being forwarded. ELAM is “embedded” within the forwarding pipeline and can capture a packet in real time without affecting performance or control plane resources. It can help answer questions like: Full Article…
Komentáře nejsou povolené u textu s názvem Basic ELAM guide
F1 vs F2 vs F2e vs F3
There are four types of F line cards available. Below is the difference between F1, F2, F2e and F3. F1 Card:- Only perform Layer-2 task. No interface can be converted to Layer3. M and F1 card can coexist in a chassis F2 line card:- Interface can be used as L2 or L3 M and F2 Full Article…
Komentáře nejsou povolené u textu s názvem F1 vs F2 vs F2e vs F3
Introduction to QoS
What is QoS? The best definition I heard is that QoS is „managed unfairness“ Different type of traffic is managed differently – make sense 😉 There are lots of QoS mechanism out there but all of them can be grouped to 3 gategories: Best effort – this is not strict DiffServ – less strict IntServ Full Article…
Komentáře nejsou povolené u textu s názvem Introduction to QoS
QoS Marking
We have different options for marking the traffic. Class of Service (CoS) – this is L2 marking. It uses the priority bits in the vlan tag 802.1Q. 3 bits make for us 8 classes available valued from 0 to 7. However cisco says 6 and 7 is reserved so 6 values left for us. When Full Article…
Komentáře nejsou povolené u textu s názvem QoS Marking
Random Early Detection (RED)
RED belongs to congestion avoidance concepts as we spoke already. RED is an industry standard. Check the picture below. We got there output queue with minimum, maximum threshold and its whole capacity. If your queue is full you start dropping packets. We dont want that. Thats why we got minimum threshold. From that point we Full Article…
Komentáře nejsou povolené u textu s názvem Random Early Detection (RED)
Netflow overview
Netflow classify packets arriving to device interface into the flows and once a flow has ended or reached maximum limit it is exported to the collector. So with flows you have a view of everything what is happening in your network. How the router classify the flows? Based on key attributes which are for example Full Article…
Komentáře nejsou povolené u textu s názvem Netflow overview