There are two primary methods to access a router or switch: a console connection, also known as out-of-band (OOB) access, and a remote connection or performing in-band access.
A console connection through a console port is the only available option to access a device without configuration settings. This method offers direct physical access to the device, allowing you to configure and troubleshoot even when network connectivity is unavailable.
As such, it is a reliable lifeline during critical setup and troubleshooting. However, one disadvantage of OOB access is that it requires physical proximity to the device.
On the other hand, once the device is configured with a management IP address, you can remotely access it. Remote access methods like Telnet and SSH provide the convenience of managing devices from remote locations with network connectivity.
Although an option, Telnet exposes communication in plaintext, making it less secure. On the other hand, SSH encrypts data transmission, protecting it from eavesdropping and tampering. Remote access is useful for off-site administrators because it allows them to control devices from any location with network connectivity.