Emergency Response and Access Control

Emergency Response and Access Control 

When it comes to ensuring safety and effectively managing critical incidents, emergency response and access control are two crucial factors. Secure Entry Solutions understand the importance of integrated solutions that provide a seamless balance between the needs of visitors and staff, while maintaining secure zones and customizing security features to meet specific requirements.

With over 90,000 organizations already choosing Keri Systems for their security needs, our solutions offer comprehensive automation of day-to-day operations, multi-site management, and proactive emergency response capabilities.

By implementing our access control systems, organizations can enhance security and prevent disasters by effectively restricting access to sensitive equipment, tightly controlling access to high-value assets, and protecting sensitive data through integration with CCTV and anti-passback systems.

Our software package enables easy management of perimeter access control, threat-level activation, CCTV integration, and auditing. With our multi-site management capabilities, organizations can effortlessly manage security across multiple locations and compile access reports for investigative purposes.

At SSA INTEGRATE, we prioritize rapid emergency response and situational awareness. Our advanced notification systems provide crucial information and situational awareness to emergency responders, enabling them to take immediate action in critical situations. With the ability to grant specific access levels to different zones or buildings, organizations can effectively manage occupancy limits and protect sensitive information and equipment.

Our cloud-based security solution (Bravo Based), offers a powerful lockdown feature that can be initiated remotely, ensuring peace of mind and enhanced security. During a lockdown, first responders are still granted access permissions to enable them to respond effectively. Once the all-clear is given, only authorized administrators have the ability to clear the lockdown.

With comprehensive integrations across security, administrative, and identity solution ecosystems, Brivo makes it easier for organizations to manage their security needs efficiently and with confidence.

Secure Entry Solutions are committed to providing top-notch emergency response and access control solutions that prioritize safety and protect against critical incidents. Partner with us to ensure the utmost security for your organization.

Enhancing Security and Preventing Disasters

Keri Systems has developed robust access control systems specifically designed for emergency responders. Our access control systems offer a wide range of features that enhance security and prevent disasters. With these systems, organizations can efficiently manage access to sensitive equipment, tightly control entry to high-value areas, and protect sensitive data.

Restricting Access to Sensitive Equipment

• Our access control systems allow organizations to restrict access to sensitive equipment, such as fire-fighting gear, ensuring that only authorized personnel can access it.

Tightly Controlling Access to High-Value Areas

• With our systems, organizations can establish strict access control measures for high-value areas, minimizing the risk of unauthorized entry and theft of valuable equipment or weaponry.

Protecting Sensitive Data through Integration

• Our access control systems integrate with CCTV and anti-passback systems to provide enhanced data protection. This integration ensures that only authorized individuals can access sensitive data, reducing the risk of data breaches.

In addition to these features, Keri Systems provides a comprehensive software package that enables efficient management of access control. With our software, organizations can easily manage perimeter access control, activate threat-level protocols, integrate with CCTV systems, and generate audit reports.

Furthermore, our access control systems offer multi-site management capabilities, allowing organizations to effectively manage security across multiple sites. This feature streamlines security operations and provides a centralized platform for compiling access reports, facilitating investigative processes.

By choosing Keri Systems’ access control systems, organizations can enhance their security measures, prevent disasters, and protect sensitive equipment and data.

Rapid Emergency Response and Situational Awareness

Keri Systems understands the critical importance of rapid emergency response and situational awareness in ensuring the safety and security of organizations. Our advanced notification systems are designed to provide real-time updates and alerts to fire fighters and police officers, enabling them to respond swiftly and effectively to emergencies.

Advance Notifications

With our advanced notification systems, organizations can receive immediate alerts about critical incidents, such as unauthorized access attempts, fire alarms, or security breaches. These advance notifications allow emergency responders to have timely information, enabling them to make informed decisions and take appropriate actions.

Dual Verification

In emergency situations, every second counts. Our dual verification feature ensures an added layer of security by requiring users to authenticate their identity through multiple verification methods. This prevents unauthorized individuals from gaining access to restricted areas and enhances the overall security of the organization.

Access Levels

Organizations often have areas with varying levels of security clearance. With our access control systems, specific access levels can be assigned to different zones, areas, or buildings, ensuring that only authorized personnel can enter certain areas. This not only helps manage occupancy limits but also protects sensitive information and equipment from unauthorized access.

Multi-Site Capabilities

For organizations with multiple locations, our systems offer seamless multi-site management capabilities. This allows for centralized control, monitoring, and reporting across all sites, ensuring consistent security protocols and efficient emergency response coordination.

Occupancy Counting

Managing occupancy limits is crucial for maintaining a safe and secure environment, especially during emergencies. Our systems enable organizations to accurately monitor and track the number of people in specific areas in real-time. This information can be used to ensure compliance with occupancy regulations and aid emergency responders in making informed decisions based on accurate occupancy counts.

With the ability to integrate with other security systems and solutions, Keri Systems offers comprehensive emergency response support for organizations of all sizes. By leveraging our advanced notification systems, dual verification capabilities, access level management, multi-site capabilities, and occupancy counting features, organizations can enhance their emergency preparedness and ensure the safety and security of their premises.

Cloud-Based Security and Peace of Mind

When it comes to ensuring the safety and security of your organization, Brivo, a leading cloud-based security solution, offers a powerful lockdown feature that brings peace of mind to both administrators and first responders. With the ability to initiate a lockdown from anywhere using a laptop, phone app, or a hardwired button in the building, Brivo’s lockdown feature provides a quick and efficient response to potential threats.

During a lockdown, first responders are still granted access permissions, ensuring their ability to swiftly enter the premises and respond effectively. This feature allows them to carry out their critical duties without any unnecessary obstacles. Once the all-clear is given, authorized administrators have the ability to clear the lockdown, restoring normal operations securely and efficiently.

Brivo goes beyond just offering a lockdown feature. Their comprehensive integrations across security, administrative, and identity solution ecosystems provide organizations with a seamless experience in managing their security needs. The cloud-based nature of Brivo’s platform enables easy access and real-time updates, making it simpler than ever to monitor and control access to your facilities.

By leveraging Brivo’s cloud-based security and innovative integrations, organizations can benefit from enhanced security measures, streamlined access control, and increased flexibility. With Brivo, you can have the peace of mind knowing that your security system is reliable and up-to-date, allowing you to focus on what matters most – your business and the safety of your employees and assets.

Authentication Vs. Authorization

Authentication and authorization are two fundamental components of information security that are used to safeguard systems (like Access Control) and data (Access Management Software). Authentication is the method by which a user or service’s identity is confirmed. At the same time, authorization determines what actions or resources a user or service is permitted to access after they have been authenticated.

Authentication involves verifying a user’s identity through a username and password, biometric authentication, or other security measures. It ensures that solely permitted individuals or systems can enter a system. Conversely, authorization entails assigning access permissions to particular resources or actions contingent upon the authenticated identity of a user or service.

The two processes work together to ensure the security of a system. If authentication is compromised, an attacker can get unauthorized system access. If authorization is not correctly configured, even authorized users may be granted excessive access privileges that can lead to data breaches. Thus, it is necessary to comprehend the difference between authentication and authorization and to verify that both are effectively configured to ensure system security.

 

What is Authentication (AuthN)?

Authentication, commonly shortened as “AuthN,” refers to verifying a user’s or entity’s identity when they seek entry into a network or system. Essentially, it validates that the user is indeed the individual they assert to be. In other words, it is the process of confirming that the user is who they claim to be. Authentication may entail something a user knows, like a password or PIN; something they have, like a security token; or something they are, like biometric authentication (e.g., fingerprint or facial recognition).

 

Purpose of Authentication

Authentication primarily identifies the user’s identity as an individual or entity attempting to access a system or resource. Authentication ensures that only authorized individuals or entities are granted access to sensitive data, systems, or resources while unauthorized access is prevented. Authentication is crucial in maintaining data and systems’ confidentiality, integrity, and availability. It prevents malicious actors from accessing sensitive information, performing unauthorized actions, or compromising the system’s security.

Authentication helps to establish accountability by ensuring that users are responsible for their actions and cannot hide behind the identities of others. Additionally, it aids in maintaining adherence to regulations and standards mandating secure access to systems and data.

Types of Authentication

Several types of authentication methods are used in information security, including:

·        Password-based Authentication: This is the most common authentication method, where users must enter a username and password to access a system or resource.

·        Multi-factor Authentication (MFA): This method combines two or more authentication factors to verify the user’s identity, for example, a password and a security token, a fingerprint and a PIN, or a smart card and a biometric scan.

·        Biometric Authentication: This method authenticates the user’s identity by leveraging distinctive physical characteristics like fingerprints, facial recognition, or iris scans.

·        Certificate-based Authentication: This method uses digital certificates to verify the user’s identity. The user’s private key is stored on a smart card or other devices, and public key infrastructure (PKI) is used to verify the certificate’s authenticity.

·        Single Sign-on (SSO): This approach permits users to authenticate once and gain access to various systems or resources without the need to re-enter their credentials.

·        Token-based Authentication: This method uses a security token or a one-time password (OTP) to authenticate the user.

 

What is Authorization (AuthZ)?

Authorization, frequently abbreviated as “AuthZ,” involves permitting or denying access to resources or actions depending on the authenticated identity of a user. In other words, authorization determines what actions or resources a user or system can access or perform after completing authentication.

Authorization typically involves assigning permissions or access levels to users or systems based on their roles, responsibilities, or request context. For example, a user with administrative privileges may be granted access to perform tasks that an ordinary user cannot perform.

 

Types of Authorization

Several common types of authorization methods are used in information security, including:

·        Role-Based Access Control (RBAC): This is one of the most commonly used authorization methods, which assigns users or systems access rights based on their roles, responsibilities, or job functions. For example, a manager might possess permission to view sensitive financial reports that regular employees are restricted from accessing.

·        Attribute-Based Access Control (ABAC): This authorization method assigns access rights based on a user’s attributes, such as their location, time of day, device used, or other contextual information. ABAC is a flexible method that allows fine-grained control over access based on specific criteria.

·        Discretionary Access Control (DAC): This authorization method empowers the resource owner to manage its access control. The owner can assign permissions to specific users or groups, and those users or groups can further delegate permissions to others.

·        Mandatory Access Control (MAC): This authorization method assigns access rights based on a security policy enforced by the system rather than the resource owner. MAC is commonly used in high-security environments such as government or military systems.

·        Rule-Based Access Control (RBAC): This authorization method employs a predetermined set of rules to ascertain access privileges. The rules may be based on specific conditions, such as the user’s department, job title, or other criteria.

 

Difference Between Authentication and Authorization

Here are the key differences between authentication and authorization:

Parameters	Authentication	Authorization
Definition	Authentication is a method of validating a user’s or system’s identity.	The process of providing or refusing access to resources or actions based on that identity is known as authorization.
Purpose	Authentication ensures that exclusively authorized users or systems can access a specific resource or execute a particular action.	Authorization specifies the access rights or permissions granted to users or systems for accessing resources or performing actions following authentication.
Objective	The objective of authentication is to confirm a user’s or system’s identity.	Authorization ensures that only authorized users or systems can access sensitive data or perform actions based on their privilege or access rights.
Aim	Authentication focuses on the user or system’s identity.	Authorization focuses on the user or system’s access rights.
Process	Authentication typically involves providing credentials such as a username and password or a security token.	Authorization, assigning permissions or access levels to users or systems based on their roles, responsibilities, or request context.
Risk	The risk of authentication is that an unauthorized user may gain access to a system.	The risk of authorization is that an authorized user may misuse their access privileges.

 

Final Thoughts

Authentication occurs before authorization, as the user or system must first be verified as legitimate before being granted access to resources or actions.

In short, authentication and authorization are two distinct but interrelated processes in information security that serve different purposes and objectives. If you want to gain more knowledge about authentication and authorization, write us ssaintegrate@gmail.com

Ways to Secure Data Centres

Data Centre Security- 11 Ways To Secure Data Centres 

In today’s world the most valuable assets is data. Together with the data centres that hold and process it, they underpin almost all facets of modern life. This makes data centres an attractive target for threat actors, due to the large and diverse amount of information that supports our national infrastructure and businesses.

The term data centre security conjures images of lines of code, hackers and firewalls. However, there is a huge requirement for physical security within a data centre too.

Data centres are used to house computer systems. They often include backup data, core data, replicated data and on the whole, are huge part of an organisation’s Disaster Recovery Strategy.

In a world where technology impacts many industries, data centres are crucial for businesses and therefore data centres security is a hot topic. Not only should data be protected from potential cyber-attacks, the physical building should be secure.

The security and resilience of your data and the infrastructure beneath it are therefore critical. High-profile data breaches and disruption to services are frequently reported, with each incident, causing operators and data owners potentially huge financial losses in regulatory fines, loss of sensitive IP, downtime, post-incident recovery, security improvements, and perhaps most valuably of all, reputation.

Cyber intrusion methodology evolves constantly, and sophisticated attackers have a strong incentive to defeat the defences you put in place. It should be assumed that at some point your defences will be breached and therefore it is also important to be able to respond proactively by detecting attacks and having measures in place to minimise the impact of any cyber security incidents.

Cyber security focuses on the prevention of data theft or destruction by malicious attacks; however, this is not enough to ensure your data centre remains safe. The building also has to be protected from physical attacks.

Here, we discuss 11 ways you can physically secure data centres.

1. Use Crash Barriers

Stop unauthorised vehicle entry with the installation of road blockers. These have been designed specifically to prevent the threat of potential intruders or terrorist attacks in high-security areas. Varying in height, these road blockers will restrict the entry of vehicles.

2. Use Bollards

Avoid anything impacting and colliding into the building by installing bollards. Install permanent bollards around the building entrances. Alternatively, you could install adjustable bollards that can be lowered to allow access to authorized vehicles.

3. Limit Entry Points

Where possible, try and limit the possible entry points to only one door. If you require additional fire doors, ensure these extra doors are exit only. Limit exterior door handles to prevent any re-entry.

4. Use Security Cameras

Surveillance cameras should be installed throughout the perimeter of the data centre. Consider installing adequate CCTV signage as this can be a physical deterrent.

5. Hire On-Site Security

Threats can happen at any time. You may consider an additional layer of physical security by hiring on-site staff. Having someone monitoring the site acts as a strong deterrent to intruders and can raise the alarm if they spot any potential issues.

6. Build The Data Centre In The Best Location

Plan the best location for your data centre. If possible, choose a location away from the company’s head office or headquarters.

Ensure the data centre is set back from the main road. Consider using landscaping to help form additional protection as trees can help obscure the building from passers-by. Avoid building data centres in locations that are prone to natural disasters such as in a flood area or an area prone to earthquakes or fires.

7. Plan The Data Centre Carefully

When you design a data centre, avoid unnecessary windows. Build walls that are extremely thick as they work an effective barrier as well as improving thermal insulation.

8. Embrace Biometric Technology

Biometric technology is increasingly popular and is now part of our every day lives. Install biometric identification systems in the building to control access. This is often a fingerprint recognition device. In addition to biometric technology, ensure multi-factor authentication is in place. This method utilises two or more authentication methods. For example, someone may use their fingerprint but will still need to type in a pin code or show an access card.

9. Install Perimeter fencing

Data Centres have access to unprecedented levels of data. It is important to protect data from digital hackers, but the data also needs to be protected in the physical sense. Therefore, security-rated fencing is of the utmost importance for these buildings and keeping data secure. As a physical security breach has the potential risk just like a digital attack would.

Perimeter security is also vital. Have strong fencing around your entire site. Ensure the gates and barriers are placed where surveillance equipment, a guard, or preferably both are in place.

This is why, at SSA INTEGRATE, we understand how vital data centre fencing is in the wider security strategy of sites. The ultimate goal is to detect potential threats early on and then allow enough time to intercept a risk or threat.

10. Use Access Control Equipment

Data centres should adopt a Zero Trust Network. This means that no one is trusted until they can prove who they are. Access control equipment is an important element of implementing this.

While it may seem simple, access lists should also be provided to ensure that only approved individuals can access data centre. Ensure these lists are kept up to date and are stored securely.

11. Install a Sophisticated Alarm System

Alarm systems are costly. However, these costs are outweighed by the potential benefits. Some systems are linked to local police stations or security companies. Others are silent, but trigger alerts to key staff. Whatever the system you choose, it will bring peace of mind.

People value physical security. They trust places that are secure when they can actually see forms of security such as gates, barriers and alarm systems.

Many companies may forget about the physical form of security when it comes to data centres as they are concentrating on the risk of cyber threats. Although cybersecurity is vital and needs to be as sophisticated as possible, teaming this up with physical security can ensure your data centre is as secure as it can be.

As data centres evolve in the future, the need for physical measures will remain vital. However, physical security measures may also evolve. Having a multi-layer approach that considers both physical and cyber elements will ensure the best protection.

Useful Measures to Prevent Unauthorized Access

Useful Measures to Prevent Unauthorized Access 

Causes of Physical Security Breaches

Unauthorized access may be gained by an outsider as well as by an in-house employee. Both physical access to a building by a stranger or entry to a server room by a staff member with no permission are examples of unauthorized physical access. Although a security system may have various loopholes, most commonly unauthorized access is gained thanks to:

·        Tailgating – i.e. an act when unauthorized people follow through a door someone who has an access card

·        Weak doors that can be easily levered or broke in through

·        Smart cards which can be easily hacked

·        Lost or stolen keys

·        Portable devices such as laptops, mobile phones and USB drives

·        Unlocked server room doors

·        Insider threat, etc.

 

Any of the above mentioned loopholes create security gaps which can be taken advantage of. Because of an unauthorized access companies may be subjected to physical theft of devices and equipment, compromise of electronic information, identity theft and vandalism. What’s more, human lives can be endangered too. Therefore, it is important that a company addresses any of the existing loopholes and prevents possible threats.

How to Combat Unauthorized Access

First and foremost, you need to define how unauthorized access can occur at your company and develop a program aimed at eradicating any possible loopholes.

Different levels of security are crucial to prevent unauthorized access. Robust access control system, employee control and emergency response help prevent unsanctioned access to facilities, devices and information.

·        Begin with perimeter security. Make sure you use fences, gates, guards and video surveillance around the perimeter.

·        By installing motion detectors and alarm systems you can attain an additional level of security.

·        Implement identification cards to verify people entering the premises, including visitors, contractors and personnel.

·        Lock up areas with sensitive information. It is also advised to enforce delay control on server room doors. Check out our guide for server room requirements.

·        Conduct background check of employees before onboarding. "Onboarding" is the process of integrating a new employee into an organization, training and orienting them.

·        Make sure you have a new hire forms checklist thanks to which you can verify your new employee’s work eligibility.

·        Set up different access control levels. Each employee should be granted permission to enter facilities depending on their role within an organization.

·        Use cable locks for computers in order to prevent theft of electronic devices.

Desktop locks are aimed at protecting computer equipment from theft.

·        Lock up sensitive files or USB drives in safes or drawers.

·        Develop an emergency plan and train employees to troubleshoot possible security issues and inform of any suspicious behavior they notice.

It is important to remember that security starts at a physical level. By implementing measures aimed at preventing unauthorized access you can protect your assets, information and personnel from internal and external security threats which otherwise might have a detrimental impact on your business.

Maintenance of the Security Bollard

Maintenance of the Security Bollard 

A high security bollard or entrance control bollard system is designed to deter or completely stop unauthorised entrants, assets or vehicles whilst enforcing the use of an access control system to ensure the ‘one token one person’ rule applies. Bollards are used to protect areas that are either completely pedestrianised, or to restrict vehicle access. Bollards also act as a great security measure for businesses and shop fronts too. Bollards are made from sturdy materials, they can sometimes be damaged or develop wear and tear over time.

The weather can have a large impact on the condition of a bollard. Going from hot to freezing temperatures can cause cracks over time. Likewise, long periods of heavy rain over the years can result in imperfections, especially where wooden bollards are concerned. That’s why it’s important to check your bollards regularly, especially if there has been an extreme change in weather. Metal bollards are less susceptible to weather damage, but over the years it may create some issues.

Bollards are usually found next to roads, or within car parks, and this means it’s not unlikely that one or two will come in contact with a vehicle. Bumps and scratches can occur, and over time this may lead to permanent damage to your bollards. A CCTV system can help to document any accidents around your perimeter and to check the severity of the damage. If any serious damage is caused, it is always best to replace the bollard.

Learning to check your bollards for damage is a great way to improve their overall maintenance. Regularly inspecting them for cracks and breaks means that they can be fixed quicker and no lasting damage will occur. If you have had your bollards for a long time, the exposure to various weather conditions may have caused them to rust or for parts to loosen. With this in mind, make sure to check them frequently. Dirt can also build-up on bollards, so giving them a quick clean every now and then will improve their performance greatly.

Safety Instructions

All personnel who are applicable for the operation of the bollard, including back up personnel, must be thoroughly familiar with the operation and safety regulations.

Any maintenance and repairs must only be implemented by certified technical personnel.

No persons and/or vehicles are allowed into the area over the blocking element when the bollard is functional.

The closing element must be extended early enough that approaching vehicles can still stop in time.

If the bollard functions are activated with neglect to the afore mentioned points the manufacturer cannot be held liable for any damages that may result to any person and/or property.

Before the maintenance work can begin all safety precautions must be adhered.

Monthly Maintenance by the Operating Personnel

After the control the stated changements in comparison to the original condition should be eliminated by corresponding counter measures.

The following points are to be visually examined:

Barrier bollard

1) Clean any contamination on the annular gap between the bollard and the cover of the standpipe

2) Check the extended blocking element for damages, e.g. impact, allow damage repair

3) Check for faultless bollard movement and pay attention to any unusual noises

Drive Unit

1) Check the hydraulic screws, oil tank and hydraulic units for leakage

2) Check the intactness of the hydraulic hoses

3) Check the oil level (level should be within the mark)

4) Check the intactness of the cover seals

First maintenance service by a machine expert

The first maintenance service should be made by a machine expert within the 1 quarter after the installation.

A. Barrier bollard

a) Clean bollard completely from dirt

b) Screw-out bollard cover and examine fixation of the hydraulic cylinder

c) Examine the piston rod and the hose connections of the cylinder on leakages through light beam of a pocket lamp.

d) Examine speed position above one -way restrictor and adjust once or if necessary the approximate direct running of the bollard running-out movement.

Bollard housing

a) Screw-off cover of the bollard housing and examine fix position of the proximity switch.

b) Clean cover and inner space of the bollard housing and clean if achievable from dirt.

c) Note, if penetrated surface water has flown above the drain channel, eliminate eventual obstructions. There should not be water in the bollard housing.

d) Note purification degree on the bottom of the bollard housing. At bigger dirt, especially in the construction phase.

Drive unit

a) Clean drive unit completely from dust and dirt.

b) Examine adjustment of the pressure limit valve for the operation pressure Manometer indication until. 50-60 bar allowed. 

Semi-Annual maintenance service by a machine expert

The semi-annual maintenance is to be performed by a machine specialist. It covers the visual examination as described under Point 1 and the following additional work:

Blocking Element

a) Clean the entire blocking element

b) Unscrew the blocking element cover and check the hydraulic cylinder mounting as well as checking the tightness of the electrical limit switches

c) Check the piston rods and hydraulic cylinder hose connections for leakage (use a torch / flashlight)

d) Check the approximate synchronisation of the bollard drive-out movement in multiple systems, if necessarily adjust the speed at the one-way restrictor.

Standpipe

a) Clean cover and interior, within reach, of any contamination

b) Check the drainage connection, if necessary remove any blockage

c) Determine the degree of pollution on the bottom of the standpipe. With large soil accumulation, particularly in the building phase, cleaning may be necessary.

Drive Unit

a) Clean the dust and dirt from the entire hydraulic unit.

b) Check the operating pressure, if necessary adjust the pressure release valve (approx. 50-60 bar)

Extensive maintenance service by a machine expert

The extensive maintenance service is after 1000 operation hours, but at least each 2 year. Additionally to the first maintenance service the following works should be made.

a) Examination of all functional components, combinations and screwing on integrity and fix position.

b) Exchange of the hydraulic liquid. Open filler cap and guide the hydraulic liquid into the sanitation container.

c) Use the unused hydraulic liquid, of the type of the first filling, to be bought from the bollard manufacturer.

d) Make functional test and if necessary, proceed to adjustment.

e) Examination of the control by an expert. Examine condition of the control and perfect working procedure of the electrical components.

The observance of the maintenance intervals and the execution of the maintenance works guarantee a free disturbances operation and maintenance of the installation.

Get in touch

Here at Expert Security we offer a range of bollards, along with maintenance service to keep them in top condition. Our maintenance cover includes a professional service, provided by our repair engineers, to regularly check your bollards. This will reduce the risk of malfunction or damage. These routine checks will be scheduled in advance and afterwards we will provide a range of detailed reports surrounding the visit. For more information on any of the security options above, or for further advice on how to protect your business premises from criminals, please contact us here or Email us on ssaintegrate@gmail.com