Which
of the following protocols provides the highest level of VPN security with a VPN connection that uses
the L2TP protocol?

A.
IPSec

B.
PPPoE

C.
PPP

D.
TFTP

Explanation:
Internet Protocol Security (IPSec) is a standard-based protocol that provides the
highest level of VPN security. IPSec can encrypt virtually
everything above the networking layer. It is used for VPN connections that use the L2TP protocol. It
secures both data and password.
IPSec cannot be used with Point-to-Point Tunneling Protocol (PPTP).
Answer option B is incorrect. Point to Point Protocol over Ethernet (PPPoE) is a specification for
establishing PPP connections through Ethernet
network adapters. It connects users on an Ethernet to the Internet through a common broadband
medium, such as a single DSL line or cable
modem. PPPoE is described in RFC 2516.
Answer option C is incorrect. Point-to-Point Protocol (PPP) is a remote access protocol commonly
used to connect to the Internet. PPP
supports compression and encryption and can be used to connect to a variety of networks. It can
connect to a network running on IPX,
TCP/IP, or NetBEUI protocol. PPP supports multi-protocol and dynamic IP assignments.
Answer option D is incorrect. Trivial File Transfer Protocol (TFTP) is a file transfer protocol, with the
functionality of a very basic form of File

Transfer Protocol (FTP). TFTP can be implemented in a very small amount of memory. It is useful for
booting computers such as routers which
did not have any data storage devices. It is used to transfer small amounts of data between hosts on
a network, such as IP phone firmware
or operating system images when a remote X Window System terminal or any other thin client boots
from a network host or server. The initial
stages of some network based installation systems (such as Solaris Jumpstart, Red Hat Kickstart and
Windows NT’s Remote Installation
Services) use TFTP to load a basic kernel that performs the actual installation. TFTP uses UDP port 69
for communication.