Browse Definitions :
Definition

EM shielding (electromagnetic shielding)

EM shielding (electromagnetic shielding) is the practice of surrounding electronics and cables with conductive or magnetic materials to guard against incoming or outgoing emissions of electromagnetic frequencies (EMF).  

EM shielding is conducted for several reasons. The most common purpose is to prevent electromagnetic interference (EMI) from affecting sensitive electronics. Metallic mesh shields are often used to protect one component from affecting another inside a particular device. In a smartphone, for example, a metallic shield protects electronics from its cellular transmitter/receiver. Radiation shields in mobile phones also decrease the amount of radio frequency (RF) energy that might be absorbed by the user. 

To increase the security of air gapped systems, EM shielding is advised. Conventionally, physical isolation and a lack of external connectivity have been considered adequate to ensure their security. However, proof-of-concept attacks have demonstrated that acoustical infection can be enabled by exploiting the electromagnetic emanations of the system’s sound card.

Air-gapping is used in the military, government and financial systems like stock exchanges. The measures are also used by reporters, activists and human rights organizations working with sensitive information. 

A number of different materials and techniques are used for EM shielding. Wires may be surrounded by a metallic foil or braid shield to block errant EMI from the cased wires. Audio speakers often have inner metallic casing to block EMI produced by the drivers so they don’t affect TVs and other electronics. Complete continuous enclosure is not necessary so long as any openings are smaller than the electromagnetic waves that need to be blocked.

Special conductive paints can be used to prevent the EMF from networks escaping the originating business to prevent eavesdropping or wireless attacks. These techniques are like a miniature Faraday cage, which can prevent signal corruption that would cause electronics to perform unexpectedly. 

Electronics may also have connections filtered for EMI by use of electronic components like capacitors, ferrules and grounded wires to minimize the effects of EMI noise -- even twisting wires together with grounds can reduce lower interference.

Magnetic materials must be used for EM shielding in environments where the magnetic fields are slowly varied below the 100Khz range as a Faraday cage-type solution is ineffective in that situation. With magnetic materials, the EMI is drawn into the magnetic field of the shielding.

This was last updated in August 2014

Continue Reading About EM shielding (electromagnetic shielding)

Networking
  • remote infrastructure management

    Remote infrastructure management, or RIM, is a comprehensive approach to handling and overseeing an organization's IT ...

  • port address translation (PAT)

    Port address translation (PAT) is a type of network address translation (NAT) that maps a network's private internal IPv4 ...

  • network fabric

    'Network fabric' is a general term used to describe underlying data network infrastructure as a whole.

Security
CIO
  • digital innovation

    Digital innovation is the adoption of modern digital technologies by a business.

  • business goals

    A business goal is an endpoint, accomplishment or target an organization wants to achieve in the short term or long term.

  • vertical SaaS (software as a service)

    Vertical SaaS describes a type of software as a service solution created for a specific industry, such as retail, financial ...

HRSoftware
  • employee onboarding and offboarding

    Employee onboarding involves all the steps needed to get a new employee successfully deployed and productive, while offboarding ...

  • skill-based learning

    Skill-based learning develops students through hands-on practice and real-world application.

  • gamification

    Gamification is a strategy that integrates entertaining and immersive gaming elements into nongame contexts to enhance engagement...

Customer Experience
  • Microsoft Dynamics 365

    Dynamics 365 is a cloud-based portfolio of business applications from Microsoft that are designed to help organizations improve ...

  • Salesforce Commerce Cloud

    Salesforce Commerce Cloud is a cloud-based suite of products that enable e-commerce businesses to set up e-commerce sites, drive ...

  • Salesforce DX

    Salesforce DX, or SFDX, is a set of software development tools that lets developers build, test and ship many kinds of ...

Close