Telecommunication

What is XMAC Expected message authentication code

Admin

Jul 16, 2024 — 1 min read

XMAC: Expected Message Authentication Code

XMAC is a term used in the context of 3GPP cellular networks, specifically in the realm of security and authentication. It stands for Expected Message Authentication Code.

How XMAC Works

XMAC is a computed value used to verify the integrity and authenticity of a message. It's derived from specific message contents and cryptographic keys. Here's a simplified breakdown:

Message Content: The message to be authenticated contains specific data fields like sequence numbers, identifiers, and other relevant information.
Cryptographic Key: A shared secret key is used for the calculation of XMAC. This key is typically derived from the security context established between the communicating entities.
XMAC Calculation: A cryptographic algorithm (e.g., hash function) is applied to the message content and the cryptographic key to generate the XMAC value.
XMAC Transmission: The calculated XMAC is appended to the message and transmitted along with it.
XMAC Verification: The receiver independently calculates the XMAC using the same algorithm, key, and message content. The calculated XMAC is compared to the received XMAC. If they match, the message is considered authentic and intact.

Purpose of XMAC

Data Integrity: Ensures that the message has not been altered during transmission.
Authentication: Verifies the identity of the sender of the message.
Replay Protection: Prevents replay attacks where an attacker retransmits a captured message.

XMAC in 3GPP

In the context of 3GPP cellular networks, XMAC is used in various security procedures, including:

NAS (Non-Access Stratum) signaling: To protect signaling messages between the UE (User Equipment) and the network.
RRC (Radio Resource Control) signaling: To protect signaling messages between the UE and the eNodeB (evolved Node B).

Key Points

XMAC is a calculated value used for message integrity and authentication.
It's derived from message content and a shared cryptographic key.
XMAC is used in various parts of the 3GPP security architecture.
Successful XMAC verification ensures message authenticity and integrity.

What is α-QPSK Alpha-QPSK

There seems to be a misunderstanding There is no standard modulation technique called "α-QPSK" or "Alpha-QPSK". Understanding QPSK It's likely you're referring to Quadrature Phase Shift Keying (QPSK), a common digital modulation technique. QPSK transmits two bits per symbol by varying the

What is ZZB (Ziv–Zakai lower bound)

Ziv-Zakai Lower Bound (ZZB) Introduction The Ziv-Zakai Lower Bound (ZZB) is a fundamental tool in estimation theory, providing a lower limit on the mean square error (MSE) of any estimator for a given parameter. Unlike the Cramér-Rao Bound (CRB), which is often asymptotically tight, the ZZB is generally tighter, especially

What is ZUC Zu Chongzhi

There seems to be a misunderstanding There is no cryptographic algorithm or protocol named ZUC Zu Chongzhi. ZUC: A Different Context It's highly likely that you're confusing ZUC with a different term. ZUC is actually a stream cipher used in 3GPP standards for mobile communication systems.

What is ZTP Zero Touch Provisioning

Zero Touch Provisioning (ZTP): A Technical Deep Dive Understanding ZTP Zero Touch Provisioning (ZTP) is an automation process that configures new network devices without manual intervention. It streamlines the deployment of network infrastructure by eliminating the need for on-site technicians to configure each device individually. How ZTP Works The core