Lots to learn about Networking part 5

I feel like this is going pretty good. I didn’t get to look at any questions last night but we did do this cross fit type of work out at the gym and like I was absolutely dead. I’m really enjoying this whole feeling sore thing and seeing results. Its great fun and is doing wonders for dad bod. I mean, I guess it didn’t really work out for me and you know, at some point id like to look and feel healthy while fitting into skinny jeans. Which I suppose is possible. You forgot that I also used this as a personal diary didn’t you? Have you seen the new Bill Gates doc? I haven’t either but I might watch it tonight. Also, my trainer keeps saying things like so uha what are you doing this weekend and like “I’m not doing anything” “I really like working out with you,” is she trying to get me to ask her out? Unclear at this time but I cant say I’m not prepared for a personal relationship like that. lol, who knows, maybe. But like gah, im so damn busy.

You know that part where I’m all “I don’t know what these answers are so I should make list” and herereere we goooo:

• OTDR – Optical Time Domain Reflectometer, an instrument that analyzes the light loss in an optical fiber in optical network trouble shooting. An OTDR injects a short, intense laser pulse into the optical fiber and measures the backscatter and reflection of light as a function of time.
• Light meter – optical power meter (OPM) is a device used measure the power in an optical signal
• Tone generator – Networks tone generator to apply a tone signal to a wire pair or single conductor, and trace with an amplifier probe. When used with the amplifier probe, the tone generator allows technicians to identify a wire within a bundle, at a cross connect or at a remote end.
• CSU/DSU – A CSU/DSU (channel service unit/data service unit) is a digital-interface device used to connect data terminal equipment (DTE), such as a router, to a digital circuit, such as a Digital Signal 1 (DS1) T1 line.

Given this information the light meter still seems plausible but its only measuring power and it says the levels are within range which leaves me questioning what exactly light loss is if its not related to the power of the signal. Assuming I’ll understand this eventually.

In the last post we learned what trap messages are in SNMPv3 monitoring and now we are seeing them again. Wondering if SOC Analysts use this a lot? Who knows. Maybe if I keep studying I will find out. Would be cool to pick up a SOC spot one day. Honestly, just trying to get in where I fit in. Sys Admin jobs would be cool as well but it seems like a hard field to break into due to a lot of old heads in the field. I have to clearly make out another list of definitions here:

• SNMP traps – (we covered this but you know) alert messages sent from a remote SNMP-enabled device to a central collector, the “SNMP manager”. A Trap might tell you that a device is overheating, for example.
• SNMP polling – involves retrieving Management Information Base (MIB) variables from devices in order to determine faulty behavior or connection problems. … During remote ping polling, enterprise-specific device MIBs are used to verify the status of the path between devices
• SNMP polling vs traps – initiated by the server and the router or switch responds to the server. An SNMP trap is initiated by the router or switch when it has information to send (usually some event happened) and does not want to wait for the server to ask for information.
• snmpwalk – is an SNMP application that uses SNMP GETNEXT requests to query a network entity for a tree of information. An object identifier (OID) may be given on the command line. This OID specifies which portion of the object identifier space will be searched using GETNEXT requests.
• SNMP version – Three versions of SNMP exist: version 1 (SNMPv1), version 2 (SNMPv2), and version 3 (SNMPv3). SNMPv1 represents the initial implementation of SNMP that functions within the specifications of the Structure of Management Information (SMI) and operates over protocols, such as User Datagram Protocol (UDP) and IP.

Given that snmpwalk seems like its user initiated this question absolutely makes sense. Which is really nice haha, even if you poll after hours its still going to use resources when you could get real time trap messages that alert you to errors much faster.

To be honest, after seeing this once I remembered the answer but I have no idea what a PAN is, the other ones im aware of. personal area network (PAN) is a computer network for interconnecting devices centered on an individual person’s workspace.

This is a question requiring a list

• Single-mode fiber – really, this, entire page is very helpful
• Cat 5e – Category 5e (Category 5 enhanced) Ethernet cables are newer than category 5 cables and support faster, more reliable data transmission through networks.
• Cat 6 – now with 6 wires
• Plenum-rated cabling – Cable that is run in the plenum spaces of buildings. In building construction, the plenum (pronounced PLEH-nuhm) is the space that is used for air circulation in heating and air conditioning systems, typically between the structural ceiling and the suspended ceiling or under a raised floor.

I’ve probably gone through all of that before but I want to be sure that I know it in case I encounter a new question on the test related to cable types.

Is this a common port usage? I’m not really sure, I could find out I suppose. SIP can be carried by several transport layer protocols including Transmission Control Protocol (TCP), User Datagram Protocol (UDP), and Stream Control Transmission Protocol (SCTP).[12][13] SIP clients typically use TCP or UDP on port numbers 5060 or 5061 for SIP traffic to servers and other endpoints. Port 5060 is commonly used for non-encrypted signaling traffic whereas port 5061 is typically used for traffic encrypted with Transport Layer Security also noted several times that its commonly used with VOIP

Any way, lets list these out for good measure

• TCP 443 – is mainly used by web servers providing HTTPS
• UDP 1720 – Port 1720 is used by the H.323 teleconferencing protocol (most commonly encountered in Microsoft NetMeeting) during call setup negotiation.
• TCP 8080 – is a place to host a secondary or alternate web server. It is commonly used for proxy and caching
• TCP 8181 – TCP is one of the main protocols in TCP/IP networks. TCP is a connection-oriented protocol, it requires handshaking to set up end-to-end communications. Only when a connection is set up user’s data can be sent bi-directionally over the connection.

Awesome to remind my self what those do. I mean, I had a vague idea but to be honest I’m not the best at direct memorization.

Friday was off to a somewhat slow start at work with lots of hardware dispatches so thankful to have a little free time to get this knocked out. Its a great day.