Pros and cons of CD-R/DVD-R/BD-R vs. USB
Nowadays there are many options to store digital data. Evidence Grade offers the physical optical media, that being CD-R, DVD-R, and BD-R. With storage capacities close to 100GB, typically this media is sufficient for the majority of applications. Evidence Grade also offers USB Cards up to 128GB and Solida State Drives up to 4TB. However, with USB drives offering larger capacity, are they any safer, or reliable than optical media?
The choice of storage medium for storing evidence depends on several factors. Each option has its advantages and considerations:
BD-R (Blu-ray Disc Recordable): BD-R discs can be write-once and have a large storage capacity ranging from 25GB up to 100GB. They are a good option for long-term archiving and can be easily labeled and organized. However, they may require specialized hardware to read and write, and their longevity is up to 50 years in controlled storage conditions or 20-30 years in normal office environments. The biggest benifit for Discs is that once the data has been written it cannot be erased or modified!
USB (Universal Serial Bus) drives: USB drives are portable, widely compatible, and offer convenient plug-and-play functionality. They come in various storage capacities and are generally durable. However, USB drives can be easily lost, damaged, or corrupted if not handled properly. Encryption and password protection can help secure the data. It should also be remembered that USB drives require an electrical charge every 5-7 years to ensure the internal memory is retained.
SSD (Solid-State Drive): SSDs provide fast data transfer speeds, high storage capacities, and are less prone to physical damage due to their lack of moving parts. They are suitable for both short-term and long-term storage. However, like USB drives, they can be lost, stolen, or suffer from data corruption if mishandled. As with USB's SSD drives require an electrical charge every 5-7 years to ensure the internal memory is retained.
Ultimately, the choice depends on the specific requirements of the evidence, including storage capacity, portability, accessibility, security, and potential future compatibility. It is often recommended to have multiple copies of evidence stored on different media and in different physical locations to minimize the risk of loss or damage.
We take a look at the advantages and disadvantages in a side by side comparison so you can decide:
| CD-R | DVD-R - 4.7GB/8.5GB | BD-R - 25GB/50GB/100GB | USB* 128GB | SSD** 1TB | |
|---|---|---|---|---|---|
| Cost per GB/100 units | $0.98 | $0.19 / $0.14 | $0.05 / $0.06 / $0.07 | $0.09 | $0.10 |
| Printable for Identification? | Yes | Yes | Yes | Difficult | Difficult |
| Large Print Area? | Yes | Yes | Yes | No | No |
| Can they transfer Virus/Malware? | Difficult | Difficult | Difficult | Once infected, transfer is easy. | Once infected, transfer is easy. |
| Can data be accidentally overwritten/deleted? | No | No | No | Easily | Easily |
| Lifetime (Years) Evidence Grade | ≥ 30 | ≥ 30 | ≥ 50 | ≤ 7 (with periodic Charging) | ≤ 7 (with periodic Charging) |
*=Sandisk 128GB Ultra 3.0 USB Drive **=Sandisk 1TB Ultra 3.0 SSD Drive
How long will data stay valid for on a USB drive ?
Memory cards, USB, and SSD drives are NOT designed for long term storage. You should always backup your data on to another device. The data will normally stay valid for a period of up to 7-10 years if stored under normal conditions. The data cells inside carry a charge which can dissipate over time. The data can be refreshed; copy all data off card and then format the card or USB drive and then restore all data to extend the data for another 7-10 years. Source: integralmemory.com