# 2023-10-12

> **Summary**

> **keywords**

> **TODO**

> **HW**\
> Find out Network device makers (Routers, switches, servers)

> **Exercise**\*

> **Next time**\
> Chapter 6. (Not in midterm)

***

## Recap

Assignment 3.\
You can use any socket libraries.

***

## SNMP & NetConf

* We will learn how to build an application that manages devices in the network.
* Under the hood of monitoring & configuration applications.
* Application layer protocol.

### Network Management

* realtime, fullfill quality of service, ....\
  \#todo : fill out

### Components of Network Management

* Managing Server : managing application is run here
* Managed devices : manageable, configurable hardware
* Data : data exchange of device state. device statistics
* Management Protocol

### Approaches to management

CLI, SNMP/MIB, YANG

#### CLI

* ex. NMAP. mainly used for port scanning.

#### SNMP/MIB

* used for manage devices.
* Simple network management protocol
* **Standardized** data exchange query and result.
* The exchanged data is called **MIB(Management Information Base)** : written in the standards.

### Two Ways to Convey MIB info

request/response mode, trap mode\
most of the times trap mode is prohibited( due to risk of malicious trap messages)

### SNMP Message types

* GetRequest
* GetNextRequest
* GetBulkRequest
*
* SetRequest
* Response
* Trap

\#todo : write about every functions.

Protocols means that there are some fields in the headers that describes some useful info.\
Why do we need protocols?\
There are so many companies that make different devices. It is impossible learn one by one how to communicate with each type of devices. Instead, we impose that

vender-specific MIBS\
every MIB object has ID, Name, ...\
MIB is transferred over UDP

\#todo : write about MIB

#### NETCONF/YANG

* more focused on configuring devices.
* The data modeling language of NetConf is YANG

What are goals ?

* actively manage / configure devices network wide.
* **atomic-commit** actions
* written in **RPC**.
* data is exchanged in XML encoded.
* reliable transport protocol (TLS) is used

NetConf can\
Standardization devekoio ed by IETF. It ensured consistent and interoperable configuarable\
Automation : Netconf is suitable for automation and orchestration.\
YANG Data models: YANG data models describle the structure and semantics of configuration data

Session initialtion call.\
Remote procedure call. & its reply\
Session clodes.

NETconf Operation\
Get-config\
get\
edit config;\
...\
\#todo : fill out operations/

MTU is packet size..
